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 - 2007, R. Byron Moore
   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 #include <acpi/amlcode.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         case ACPI_TYPE_DEVICE:
 139
 140                 if (object->device.gpe_block) {
 141                         (void)acpi_ev_delete_gpe_block(object->device.
 142                                                        gpe_block);
 143                 }
 144
 145                 /* Walk the handler list for this device */
 146
 147                 handler_desc = object->device.handler;
 148                 while (handler_desc) {
 149                         next_desc = handler_desc->address_space.next;
 150                         acpi_ut_remove_reference(handler_desc);
 151                         handler_desc = next_desc;
 152                 }
 153                 break;
 154
 155         case ACPI_TYPE_MUTEX:
 156
 157                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 158                                   "***** Mutex %p, OS Mutex %p\n",
 159                                   object, object->mutex.os_mutex));
 160
 161                 if (object->mutex.os_mutex == acpi_gbl_global_lock_mutex) {
 162
 163                         /* Global Lock has extra semaphore */
 164
 165                         (void)
 166                             acpi_os_delete_semaphore
 167                             (acpi_gbl_global_lock_semaphore);
 168                         acpi_gbl_global_lock_semaphore = NULL;
 169
 170                         acpi_os_delete_mutex(object->mutex.os_mutex);
 171                         acpi_gbl_global_lock_mutex = NULL;
 172                 } else {
 173                         acpi_ex_unlink_mutex(object);
 174                         acpi_os_delete_mutex(object->mutex.os_mutex);
 175                 }
 176                 break;
 177
 178         case ACPI_TYPE_EVENT:
 179
 180                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 181                                   "***** Event %p, OS Semaphore %p\n",
 182                                   object, object->event.os_semaphore));
 183
 184                 (void)acpi_os_delete_semaphore(object->event.os_semaphore);
 185                 object->event.os_semaphore = NULL;
 186                 break;
 187
 188         case ACPI_TYPE_METHOD:
 189
 190                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 191                                   "***** Method %p\n", object));
 192
 193                 /* Delete the method mutex if it exists */
 194
 195                 if (object->method.mutex) {
 196                         acpi_os_delete_mutex(object->method.mutex->mutex.
 197                                              os_mutex);
 198                         acpi_ut_delete_object_desc(object->method.mutex);
 199                         object->method.mutex = NULL;
 200                 }
 201                 break;
 202
 203         case ACPI_TYPE_REGION:
 204
 205                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 206                                   "***** Region %p\n", object));
 207
 208                 second_desc = acpi_ns_get_secondary_object(object);
 209                 if (second_desc) {
 210                         /*
 211                          * Free the region_context if and only if the handler is one of the
 212                          * default handlers -- and therefore, we created the context object
 213                          * locally, it was not created by an external caller.
 214                          */
 215                         handler_desc = object->region.handler;
 216                         if (handler_desc) {
 217                                 if (handler_desc->address_space.handler_flags &
 218                                     ACPI_ADDR_HANDLER_DEFAULT_INSTALLED) {
 219
 220                                         /* Deactivate region and free region context */
 221
 222                                         if (handler_desc->address_space.setup) {
 223                                                 (void)handler_desc->
 224                                                     address_space.setup(object,
 225                                                                         ACPI_REGION_DEACTIVATE,
 226                                                                         handler_desc->
 227                                                                         address_space.
 228                                                                         context,
 229                                                                         &second_desc->
 230                                                                         extra.
 231                                                                         region_context);
 232                                         }
 233                                 }
 234
 235                                 acpi_ut_remove_reference(handler_desc);
 236                         }
 237
 238                         /* Now we can free the Extra object */
 239
 240                         acpi_ut_delete_object_desc(second_desc);
 241                 }
 242                 break;
 243
 244         case ACPI_TYPE_BUFFER_FIELD:
 245
 246                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 247                                   "***** Buffer Field %p\n", object));
 248
 249                 second_desc = acpi_ns_get_secondary_object(object);
 250                 if (second_desc) {
 251                         acpi_ut_delete_object_desc(second_desc);
 252                 }
 253                 break;
 254
 255         default:
 256                 break;
 257         }
 258
 259         /* Free any allocated memory (pointer within the object) found above */
 260
 261         if (obj_pointer) {
 262                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 263                                   "Deleting Object Subptr %p\n", obj_pointer));
 264                 ACPI_FREE(obj_pointer);
 265         }
 266
 267         /* Now the object can be safely deleted */
 268
 269         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS, "Deleting Object %p [%s]\n",
 270                           object, acpi_ut_get_object_type_name(object)));
 271
 272         acpi_ut_delete_object_desc(object);
 273         return_VOID;
 274 }
 275
 276 /*******************************************************************************
 277  *
 278  * FUNCTION:    acpi_ut_delete_internal_object_list
 279  *
 280  * PARAMETERS:  obj_list        - Pointer to the list to be deleted
 281  *
 282  * RETURN:      None
 283  *
 284  * DESCRIPTION: This function deletes an internal object list, including both
 285  *              simple objects and package objects
 286  *
 287  ******************************************************************************/
 288
 289 void acpi_ut_delete_internal_object_list(union acpi_operand_object **obj_list)
 290 {
 291         union acpi_operand_object **internal_obj;
 292
 293         ACPI_FUNCTION_TRACE(ut_delete_internal_object_list);
 294
 295         /* Walk the null-terminated internal list */
 296
 297         for (internal_obj = obj_list; *internal_obj; internal_obj++) {
 298                 acpi_ut_remove_reference(*internal_obj);
 299         }
 300
 301         /* Free the combined parameter pointer list and object array */
 302
 303         ACPI_FREE(obj_list);
 304         return_VOID;
 305 }
 306
 307 /*******************************************************************************
 308  *
 309  * FUNCTION:    acpi_ut_update_ref_count
 310  *
 311  * PARAMETERS:  Object          - Object whose ref count is to be updated
 312  *              Action          - What to do
 313  *
 314  * RETURN:      New ref count
 315  *
 316  * DESCRIPTION: Modify the ref count and return it.
 317  *
 318  ******************************************************************************/
 319
 320 static void
 321 acpi_ut_update_ref_count(union acpi_operand_object *object, u32 action)
 322 {
 323         u16 count;
 324         u16 new_count;
 325
 326         ACPI_FUNCTION_NAME(ut_update_ref_count);
 327
 328         if (!object) {
 329                 return;
 330         }
 331
 332         count = object->common.reference_count;
 333         new_count = count;
 334
 335         /*
 336          * Perform the reference count action (increment, decrement, force delete)
 337          */
 338         switch (action) {
 339         case REF_INCREMENT:
 340
 341                 new_count++;
 342                 object->common.reference_count = new_count;
 343
 344                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 345                                   "Obj %p Refs=%X, [Incremented]\n",
 346                                   object, new_count));
 347                 break;
 348
 349         case REF_DECREMENT:
 350
 351                 if (count < 1) {
 352                         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 353                                           "Obj %p Refs=%X, can't decrement! (Set to 0)\n",
 354                                           object, new_count));
 355
 356                         new_count = 0;
 357                 } else {
 358                         new_count--;
 359
 360                         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 361                                           "Obj %p Refs=%X, [Decremented]\n",
 362                                           object, new_count));
 363                 }
 364
 365                 if (ACPI_GET_OBJECT_TYPE(object) == ACPI_TYPE_METHOD) {
 366                         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 367                                           "Method Obj %p Refs=%X, [Decremented]\n",
 368                                           object, new_count));
 369                 }
 370
 371                 object->common.reference_count = new_count;
 372                 if (new_count == 0) {
 373                         acpi_ut_delete_internal_obj(object);
 374                 }
 375                 break;
 376
 377         case REF_FORCE_DELETE:
 378
 379                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 380                                   "Obj %p Refs=%X, Force delete! (Set to 0)\n",
 381                                   object, count));
 382
 383                 new_count = 0;
 384                 object->common.reference_count = new_count;
 385                 acpi_ut_delete_internal_obj(object);
 386                 break;
 387
 388         default:
 389
 390                 ACPI_ERROR((AE_INFO, "Unknown action (%X)", action));
 391                 break;
 392         }
 393
 394         /*
 395          * Sanity check the reference count, for debug purposes only.
 396          * (A deleted object will have a huge reference count)
 397          */
 398         if (count > ACPI_MAX_REFERENCE_COUNT) {
 399                 ACPI_WARNING((AE_INFO,
 400                               "Large Reference Count (%X) in object %p", count,
 401                               object));
 402         }
 403 }
 404
 405 /*******************************************************************************
 406  *
 407  * FUNCTION:    acpi_ut_update_object_reference
 408  *
 409  * PARAMETERS:  Object              - Increment ref count for this object
 410  *                                    and all sub-objects
 411  *              Action              - Either REF_INCREMENT or REF_DECREMENT or
 412  *                                    REF_FORCE_DELETE
 413  *
 414  * RETURN:      Status
 415  *
 416  * DESCRIPTION: Increment the object reference count
 417  *
 418  * Object references are incremented when:
 419  * 1) An object is attached to a Node (namespace object)
 420  * 2) An object is copied (all subobjects must be incremented)
 421  *
 422  * Object references are decremented when:
 423  * 1) An object is detached from an Node
 424  *
 425  ******************************************************************************/
 426
 427 acpi_status
 428 acpi_ut_update_object_reference(union acpi_operand_object *object, u16 action)
 429 {
 430         acpi_status status = AE_OK;
 431         union acpi_generic_state *state_list = NULL;
 432         union acpi_operand_object *next_object = NULL;
 433         union acpi_generic_state *state;
 434         acpi_native_uint i;
 435
 436         ACPI_FUNCTION_TRACE_PTR(ut_update_object_reference, object);
 437
 438         while (object) {
 439
 440                 /* Make sure that this isn't a namespace handle */
 441
 442                 if (ACPI_GET_DESCRIPTOR_TYPE(object) == ACPI_DESC_TYPE_NAMED) {
 443                         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 444                                           "Object %p is NS handle\n", object));
 445                         return_ACPI_STATUS(AE_OK);
 446                 }
 447
 448                 /*
 449                  * All sub-objects must have their reference count incremented also.
 450                  * Different object types have different subobjects.
 451                  */
 452                 switch (ACPI_GET_OBJECT_TYPE(object)) {
 453                 case ACPI_TYPE_DEVICE:
 454                 case ACPI_TYPE_PROCESSOR:
 455                 case ACPI_TYPE_POWER:
 456                 case ACPI_TYPE_THERMAL:
 457
 458                         /* Update the notify objects for these types (if present) */
 459
 460                         acpi_ut_update_ref_count(object->common_notify.
 461                                                  system_notify, action);
 462                         acpi_ut_update_ref_count(object->common_notify.
 463                                                  device_notify, action);
 464                         break;
 465
 466                 case ACPI_TYPE_PACKAGE:
 467                         /*
 468                          * We must update all the sub-objects of the package,
 469                          * each of whom may have their own sub-objects.
 470                          */
 471                         for (i = 0; i < object->package.count; i++) {
 472                                 /*
 473                                  * Push each element onto the stack for later processing.
 474                                  * Note: There can be null elements within the package,
 475                                  * these are simply ignored
 476                                  */
 477                                 status =
 478                                     acpi_ut_create_update_state_and_push
 479                                     (object->package.elements[i], action,
 480                                      &state_list);
 481                                 if (ACPI_FAILURE(status)) {
 482                                         goto error_exit;
 483                                 }
 484                         }
 485                         break;
 486
 487                 case ACPI_TYPE_BUFFER_FIELD:
 488
 489                         next_object = object->buffer_field.buffer_obj;
 490                         break;
 491
 492                 case ACPI_TYPE_LOCAL_REGION_FIELD:
 493
 494                         next_object = object->field.region_obj;
 495                         break;
 496
 497                 case ACPI_TYPE_LOCAL_BANK_FIELD:
 498
 499                         next_object = object->bank_field.bank_obj;
 500                         status =
 501                             acpi_ut_create_update_state_and_push(object->
 502                                                                  bank_field.
 503                                                                  region_obj,
 504                                                                  action,
 505                                                                  &state_list);
 506                         if (ACPI_FAILURE(status)) {
 507                                 goto error_exit;
 508                         }
 509                         break;
 510
 511                 case ACPI_TYPE_LOCAL_INDEX_FIELD:
 512
 513                         next_object = object->index_field.index_obj;
 514                         status =
 515                             acpi_ut_create_update_state_and_push(object->
 516                                                                  index_field.
 517                                                                  data_obj,
 518                                                                  action,
 519                                                                  &state_list);
 520                         if (ACPI_FAILURE(status)) {
 521                                 goto error_exit;
 522                         }
 523                         break;
 524
 525                 case ACPI_TYPE_LOCAL_REFERENCE:
 526                         /*
 527                          * The target of an Index (a package, string, or buffer) must track
 528                          * changes to the ref count of the index.
 529                          */
 530                         if (object->reference.opcode == AML_INDEX_OP) {
 531                                 next_object = object->reference.object;
 532                         }
 533                         break;
 534
 535                 case ACPI_TYPE_REGION:
 536                 default:
 537                         break;  /* No subobjects for all other types */
 538                 }
 539
 540                 /*
 541                  * Now we can update the count in the main object. This can only
 542                  * happen after we update the sub-objects in case this causes the
 543                  * main object to be deleted.
 544                  */
 545                 acpi_ut_update_ref_count(object, action);
 546                 object = NULL;
 547
 548                 /* Move on to the next object to be updated */
 549
 550                 if (next_object) {
 551                         object = next_object;
 552                         next_object = NULL;
 553                 } else if (state_list) {
 554                         state = acpi_ut_pop_generic_state(&state_list);
 555                         object = state->update.object;
 556                         acpi_ut_delete_generic_state(state);
 557                 }
 558         }
 559
 560         return_ACPI_STATUS(AE_OK);
 561
 562       error_exit:
 563
 564         ACPI_EXCEPTION((AE_INFO, status,
 565                         "Could not update object reference count"));
 566
 567         return_ACPI_STATUS(status);
 568 }
 569
 570 /*******************************************************************************
 571  *
 572  * FUNCTION:    acpi_ut_add_reference
 573  *
 574  * PARAMETERS:  Object          - Object whose reference count is to be
 575  *                                incremented
 576  *
 577  * RETURN:      None
 578  *
 579  * DESCRIPTION: Add one reference to an ACPI object
 580  *
 581  ******************************************************************************/
 582
 583 void acpi_ut_add_reference(union acpi_operand_object *object)
 584 {
 585
 586         ACPI_FUNCTION_TRACE_PTR(ut_add_reference, object);
 587
 588         /* Ensure that we have a valid object */
 589
 590         if (!acpi_ut_valid_internal_object(object)) {
 591                 return_VOID;
 592         }
 593
 594         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 595                           "Obj %p Current Refs=%X [To Be Incremented]\n",
 596                           object, object->common.reference_count));
 597
 598         /* Increment the reference count */
 599
 600         (void)acpi_ut_update_object_reference(object, REF_INCREMENT);
 601         return_VOID;
 602 }
 603
 604 /*******************************************************************************
 605  *
 606  * FUNCTION:    acpi_ut_remove_reference
 607  *
 608  * PARAMETERS:  Object         - Object whose ref count will be decremented
 609  *
 610  * RETURN:      None
 611  *
 612  * DESCRIPTION: Decrement the reference count of an ACPI internal object
 613  *
 614  ******************************************************************************/
 615
 616 void acpi_ut_remove_reference(union acpi_operand_object *object)
 617 {
 618
 619         ACPI_FUNCTION_TRACE_PTR(ut_remove_reference, object);
 620
 621         /*
 622          * Allow a NULL pointer to be passed in, just ignore it. This saves
 623          * each caller from having to check. Also, ignore NS nodes.
 624          *
 625          */
 626         if (!object ||
 627             (ACPI_GET_DESCRIPTOR_TYPE(object) == ACPI_DESC_TYPE_NAMED)) {
 628                 return_VOID;
 629         }
 630
 631         /* Ensure that we have a valid object */
 632
 633         if (!acpi_ut_valid_internal_object(object)) {
 634                 return_VOID;
 635         }
 636
 637         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 638                           "Obj %p Current Refs=%X [To Be Decremented]\n",
 639                           object, object->common.reference_count));
 640
 641         /*
 642          * Decrement the reference count, and only actually delete the object
 643          * if the reference count becomes 0. (Must also decrement the ref count
 644          * of all subobjects!)
 645          */
 646         (void)acpi_ut_update_object_reference(object, REF_DECREMENT);
 647         return_VOID;
 648 }