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 - 2004, 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
  45 #include <acpi/acpi.h>
  46 #include <acpi/acinterp.h>
  47 #include <acpi/acnamesp.h>
  48 #include <acpi/acevents.h>
  49
  50 #define _COMPONENT          ACPI_UTILITIES
  51          ACPI_MODULE_NAME    ("utdelete")
  52
  53
  54 /*******************************************************************************
  55  *
  56  * FUNCTION:    acpi_ut_delete_internal_obj
  57  *
  58  * PARAMETERS:  *Object        - Pointer to the list to be deleted
  59  *
  60  * RETURN:      None
  61  *
  62  * DESCRIPTION: Low level object deletion, after reference counts have been
  63  *              updated (All reference counts, including sub-objects!)
  64  *
  65  ******************************************************************************/
  66
  67 void
  68 acpi_ut_delete_internal_obj (
  69         union acpi_operand_object       *object)
  70 {
  71         void                            *obj_pointer = NULL;
  72         union acpi_operand_object       *handler_desc;
  73         union acpi_operand_object       *second_desc;
  74         union acpi_operand_object       *next_desc;
  75
  76
  77         ACPI_FUNCTION_TRACE_PTR ("ut_delete_internal_obj", object);
  78
  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, "**** String %p, ptr %p\n",
  92                         object, object->string.pointer));
  93
  94                 /* Free the actual string buffer */
  95
  96                 if (!(object->common.flags & AOPOBJ_STATIC_POINTER)) {
  97                         /* But only if it is NOT a pointer into an ACPI table */
  98
  99                         obj_pointer = object->string.pointer;
 100                 }
 101                 break;
 102
 103
 104         case ACPI_TYPE_BUFFER:
 105
 106                 ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS, "**** Buffer %p, ptr %p\n",
 107                         object, object->buffer.pointer));
 108
 109                 /* Free the actual buffer */
 110
 111                 if (!(object->common.flags & AOPOBJ_STATIC_POINTER)) {
 112                         /* But only if it is NOT a pointer into an ACPI table */
 113
 114                         obj_pointer = object->buffer.pointer;
 115                 }
 116                 break;
 117
 118
 119         case ACPI_TYPE_PACKAGE:
 120
 121                 ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS, " **** Package of count %X\n",
 122                         object->package.count));
 123
 124                 /*
 125                  * Elements of the package are not handled here, they are deleted
 126                  * separately
 127                  */
 128
 129                 /* Free the (variable length) element pointer array */
 130
 131                 obj_pointer = object->package.elements;
 132                 break;
 133
 134
 135         case ACPI_TYPE_DEVICE:
 136
 137                 if (object->device.gpe_block) {
 138                         (void) acpi_ev_delete_gpe_block (object->device.gpe_block);
 139                 }
 140
 141                 /* Walk the handler list for this device */
 142
 143                 handler_desc = object->device.handler;
 144                 while (handler_desc) {
 145                         next_desc = handler_desc->address_space.next;
 146                         acpi_ut_remove_reference (handler_desc);
 147                         handler_desc = next_desc;
 148                 }
 149                 break;
 150
 151
 152         case ACPI_TYPE_MUTEX:
 153
 154                 ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS, "***** Mutex %p, Semaphore %p\n",
 155                         object, object->mutex.semaphore));
 156
 157                 acpi_ex_unlink_mutex (object);
 158                 (void) acpi_os_delete_semaphore (object->mutex.semaphore);
 159                 break;
 160
 161
 162         case ACPI_TYPE_EVENT:
 163
 164                 ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS, "***** Event %p, Semaphore %p\n",
 165                         object, object->event.semaphore));
 166
 167                 (void) acpi_os_delete_semaphore (object->event.semaphore);
 168                 object->event.semaphore = NULL;
 169                 break;
 170
 171
 172         case ACPI_TYPE_METHOD:
 173
 174                 ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS, "***** Method %p\n", object));
 175
 176                 /* Delete the method semaphore if it exists */
 177
 178                 if (object->method.semaphore) {
 179                         (void) acpi_os_delete_semaphore (object->method.semaphore);
 180                         object->method.semaphore = NULL;
 181                 }
 182                 break;
 183
 184
 185         case ACPI_TYPE_REGION:
 186
 187                 ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS, "***** Region %p\n", object));
 188
 189                 second_desc = acpi_ns_get_secondary_object (object);
 190                 if (second_desc) {
 191                         /*
 192                          * Free the region_context if and only if the handler is one of the
 193                          * default handlers -- and therefore, we created the context object
 194                          * locally, it was not created by an external caller.
 195                          */
 196                         handler_desc = object->region.handler;
 197                         if (handler_desc) {
 198                                 if (handler_desc->address_space.hflags & ACPI_ADDR_HANDLER_DEFAULT_INSTALLED) {
 199                                         obj_pointer = second_desc->extra.region_context;
 200                                 }
 201
 202                                 acpi_ut_remove_reference (handler_desc);
 203                         }
 204
 205                         /* Now we can free the Extra object */
 206
 207                         acpi_ut_delete_object_desc (second_desc);
 208                 }
 209                 break;
 210
 211
 212         case ACPI_TYPE_BUFFER_FIELD:
 213
 214                 ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS, "***** Buffer Field %p\n", object));
 215
 216                 second_desc = acpi_ns_get_secondary_object (object);
 217                 if (second_desc) {
 218                         acpi_ut_delete_object_desc (second_desc);
 219                 }
 220                 break;
 221
 222
 223         default:
 224                 break;
 225         }
 226
 227         /* Free any allocated memory (pointer within the object) found above */
 228
 229         if (obj_pointer) {
 230                 ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS, "Deleting Object Subptr %p\n",
 231                                 obj_pointer));
 232                 ACPI_MEM_FREE (obj_pointer);
 233         }
 234
 235         /* Now the object can be safely deleted */
 236
 237         ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS, "Deleting Object %p [%s]\n",
 238                         object, acpi_ut_get_object_type_name (object)));
 239
 240         acpi_ut_delete_object_desc (object);
 241         return_VOID;
 242 }
 243
 244
 245 /*******************************************************************************
 246  *
 247  * FUNCTION:    acpi_ut_delete_internal_object_list
 248  *
 249  * PARAMETERS:  *obj_list       - Pointer to the list to be deleted
 250  *
 251  * RETURN:      None
 252  *
 253  * DESCRIPTION: This function deletes an internal object list, including both
 254  *              simple objects and package objects
 255  *
 256  ******************************************************************************/
 257
 258 void
 259 acpi_ut_delete_internal_object_list (
 260         union acpi_operand_object       **obj_list)
 261 {
 262         union acpi_operand_object       **internal_obj;
 263
 264
 265         ACPI_FUNCTION_TRACE ("ut_delete_internal_object_list");
 266
 267
 268         /* Walk the null-terminated internal list */
 269
 270         for (internal_obj = obj_list; *internal_obj; internal_obj++) {
 271                 acpi_ut_remove_reference (*internal_obj);
 272         }
 273
 274         /* Free the combined parameter pointer list and object array */
 275
 276         ACPI_MEM_FREE (obj_list);
 277         return_VOID;
 278 }
 279
 280
 281 /*******************************************************************************
 282  *
 283  * FUNCTION:    acpi_ut_update_ref_count
 284  *
 285  * PARAMETERS:  *Object         - Object whose ref count is to be updated
 286  *              Action          - What to do
 287  *
 288  * RETURN:      New ref count
 289  *
 290  * DESCRIPTION: Modify the ref count and return it.
 291  *
 292  ******************************************************************************/
 293
 294 static void
 295 acpi_ut_update_ref_count (
 296         union acpi_operand_object       *object,
 297         u32                             action)
 298 {
 299         u16                             count;
 300         u16                             new_count;
 301
 302
 303         ACPI_FUNCTION_NAME ("ut_update_ref_count");
 304
 305
 306         if (!object) {
 307                 return;
 308         }
 309
 310         count = object->common.reference_count;
 311         new_count = count;
 312
 313         /*
 314          * Perform the reference count action (increment, decrement, or force delete)
 315          */
 316         switch (action) {
 317
 318         case REF_INCREMENT:
 319
 320                 new_count++;
 321                 object->common.reference_count = new_count;
 322
 323                 ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS, "Obj %p Refs=%X, [Incremented]\n",
 324                         object, new_count));
 325                 break;
 326
 327
 328         case REF_DECREMENT:
 329
 330                 if (count < 1) {
 331                         ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS, "Obj %p Refs=%X, can't decrement! (Set to 0)\n",
 332                                 object, new_count));
 333
 334                         new_count = 0;
 335                 }
 336                 else {
 337                         new_count--;
 338
 339                         ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS, "Obj %p Refs=%X, [Decremented]\n",
 340                                 object, new_count));
 341                 }
 342
 343                 if (ACPI_GET_OBJECT_TYPE (object) == ACPI_TYPE_METHOD) {
 344                         ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS, "Method Obj %p Refs=%X, [Decremented]\n",
 345                                 object, new_count));
 346                 }
 347
 348                 object->common.reference_count = new_count;
 349                 if (new_count == 0) {
 350                         acpi_ut_delete_internal_obj (object);
 351                 }
 352
 353                 break;
 354
 355
 356         case REF_FORCE_DELETE:
 357
 358                 ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS, "Obj %p Refs=%X, Force delete! (Set to 0)\n",
 359                         object, count));
 360
 361                 new_count = 0;
 362                 object->common.reference_count = new_count;
 363                 acpi_ut_delete_internal_obj (object);
 364                 break;
 365
 366
 367         default:
 368
 369                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Unknown action (%X)\n", action));
 370                 break;
 371         }
 372
 373         /*
 374          * Sanity check the reference count, for debug purposes only.
 375          * (A deleted object will have a huge reference count)
 376          */
 377         if (count > ACPI_MAX_REFERENCE_COUNT) {
 378
 379                 ACPI_DEBUG_PRINT ((ACPI_DB_WARN,
 380                         "**** Warning **** Large Reference Count (%X) in object %p\n\n",
 381                         count, object));
 382         }
 383
 384         return;
 385 }
 386
 387
 388 /*******************************************************************************
 389  *
 390  * FUNCTION:    acpi_ut_update_object_reference
 391  *
 392  * PARAMETERS:  *Object             - Increment ref count for this object
 393  *                                    and all sub-objects
 394  *              Action              - Either REF_INCREMENT or REF_DECREMENT or
 395  *                                    REF_FORCE_DELETE
 396  *
 397  * RETURN:      Status
 398  *
 399  * DESCRIPTION: Increment the object reference count
 400  *
 401  * Object references are incremented when:
 402  * 1) An object is attached to a Node (namespace object)
 403  * 2) An object is copied (all subobjects must be incremented)
 404  *
 405  * Object references are decremented when:
 406  * 1) An object is detached from an Node
 407  *
 408  ******************************************************************************/
 409
 410 acpi_status
 411 acpi_ut_update_object_reference (
 412         union acpi_operand_object       *object,
 413         u16                             action)
 414 {
 415         acpi_status                     status;
 416         u32                             i;
 417         union acpi_generic_state         *state_list = NULL;
 418         union acpi_generic_state         *state;
 419         union acpi_operand_object        *tmp;
 420
 421         ACPI_FUNCTION_TRACE_PTR ("ut_update_object_reference", object);
 422
 423
 424         /* Ignore a null object ptr */
 425
 426         if (!object) {
 427                 return_ACPI_STATUS (AE_OK);
 428         }
 429
 430         /* Make sure that this isn't a namespace handle */
 431
 432         if (ACPI_GET_DESCRIPTOR_TYPE (object) == ACPI_DESC_TYPE_NAMED) {
 433                 ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS, "Object %p is NS handle\n", object));
 434                 return_ACPI_STATUS (AE_OK);
 435         }
 436
 437         state = acpi_ut_create_update_state (object, action);
 438
 439         while (state) {
 440                 object = state->update.object;
 441                 action = state->update.value;
 442                 acpi_ut_delete_generic_state (state);
 443
 444                 /*
 445                  * All sub-objects must have their reference count incremented also.
 446                  * Different object types have different subobjects.
 447                  */
 448                 switch (ACPI_GET_OBJECT_TYPE (object)) {
 449                 case ACPI_TYPE_DEVICE:
 450
 451                         tmp = object->device.system_notify;
 452                         if (tmp && (tmp->common.reference_count <= 1) && action == REF_DECREMENT)
 453                                 object->device.system_notify = NULL;
 454                         acpi_ut_update_ref_count (tmp, action);
 455
 456                         tmp = object->device.device_notify;
 457                         if (tmp && (tmp->common.reference_count <= 1) && action == REF_DECREMENT)
 458                                 object->device.device_notify = NULL;
 459                         acpi_ut_update_ref_count (tmp, action);
 460
 461                         break;
 462
 463
 464                 case ACPI_TYPE_PACKAGE:
 465
 466                         /*
 467                          * We must update all the sub-objects of the package
 468                          * (Each of whom may have their own sub-objects, etc.
 469                          */
 470                         for (i = 0; i < object->package.count; i++) {
 471                                 /*
 472                                  * Push each element onto the stack for later processing.
 473                                  * Note: There can be null elements within the package,
 474                                  * these are simply ignored
 475                                  */
 476                                 status = acpi_ut_create_update_state_and_push (
 477                                                  object->package.elements[i], action, &state_list);
 478                                 if (ACPI_FAILURE (status)) {
 479                                         goto error_exit;
 480                                 }
 481
 482                                 tmp = object->package.elements[i];
 483                                 if (tmp && (tmp->common.reference_count <= 1)  && action == REF_DECREMENT)
 484                                         object->package.elements[i] = NULL;
 485                         }
 486                         break;
 487
 488
 489                 case ACPI_TYPE_BUFFER_FIELD:
 490
 491                         status = acpi_ut_create_update_state_and_push (
 492                                          object->buffer_field.buffer_obj, action, &state_list);
 493                         if (ACPI_FAILURE (status)) {
 494                                 goto error_exit;
 495                         }
 496
 497                         tmp = object->buffer_field.buffer_obj;
 498                         if ( tmp && (tmp->common.reference_count <= 1)  && action == REF_DECREMENT)
 499                                 object->buffer_field.buffer_obj = NULL;
 500                         break;
 501
 502
 503                 case ACPI_TYPE_LOCAL_REGION_FIELD:
 504
 505                         status = acpi_ut_create_update_state_and_push (
 506                                          object->field.region_obj, action, &state_list);
 507                         if (ACPI_FAILURE (status)) {
 508                                 goto error_exit;
 509                         }
 510
 511                         tmp = object->field.region_obj;
 512                         if ( tmp && (tmp->common.reference_count <= 1)  && action == REF_DECREMENT)
 513                                 object->field.region_obj = NULL;
 514                    break;
 515
 516
 517                 case ACPI_TYPE_LOCAL_BANK_FIELD:
 518
 519                         status = acpi_ut_create_update_state_and_push (
 520                                          object->bank_field.bank_obj, action, &state_list);
 521                         if (ACPI_FAILURE (status)) {
 522                                 goto error_exit;
 523                         }
 524
 525                         tmp = object->bank_field.bank_obj;
 526                         if ( tmp && (tmp->common.reference_count <= 1)  && action == REF_DECREMENT)
 527                                 object->bank_field.bank_obj = NULL;
 528
 529                         status = acpi_ut_create_update_state_and_push (
 530                                          object->bank_field.region_obj, action, &state_list);
 531                         if (ACPI_FAILURE (status)) {
 532                                 goto error_exit;
 533                         }
 534
 535                         tmp = object->bank_field.region_obj;
 536                         if ( tmp && (tmp->common.reference_count <= 1)  && action == REF_DECREMENT)
 537                                 object->bank_field.region_obj = NULL;
 538                         break;
 539
 540
 541                 case ACPI_TYPE_LOCAL_INDEX_FIELD:
 542
 543                         status = acpi_ut_create_update_state_and_push (
 544                                          object->index_field.index_obj, action, &state_list);
 545                         if (ACPI_FAILURE (status)) {
 546                                 goto error_exit;
 547                         }
 548
 549                         tmp = object->index_field.index_obj;
 550                         if ( tmp && (tmp->common.reference_count <= 1)  && action == REF_DECREMENT)
 551                                 object->index_field.index_obj = NULL;
 552
 553                         status = acpi_ut_create_update_state_and_push (
 554                                          object->index_field.data_obj, action, &state_list);
 555                         if (ACPI_FAILURE (status)) {
 556                                 goto error_exit;
 557                         }
 558
 559                         tmp = object->index_field.data_obj;
 560                         if ( tmp && (tmp->common.reference_count <= 1)  && action == REF_DECREMENT)
 561                                 object->index_field.data_obj = NULL;
 562                         break;
 563
 564
 565                 case ACPI_TYPE_REGION:
 566                 case ACPI_TYPE_LOCAL_REFERENCE:
 567                 default:
 568
 569                         /* No subobjects */
 570                         break;
 571                 }
 572
 573                 /*
 574                  * Now we can update the count in the main object.  This can only
 575                  * happen after we update the sub-objects in case this causes the
 576                  * main object to be deleted.
 577                  */
 578                 acpi_ut_update_ref_count (object, action);
 579
 580                 /* Move on to the next object to be updated */
 581
 582                 state = acpi_ut_pop_generic_state (&state_list);
 583         }
 584
 585         return_ACPI_STATUS (AE_OK);
 586
 587
 588 error_exit:
 589
 590         ACPI_REPORT_ERROR (("Could not update object reference count, %s\n",
 591                 acpi_format_exception (status)));
 592
 593         return_ACPI_STATUS (status);
 594 }
 595
 596
 597 /*******************************************************************************
 598  *
 599  * FUNCTION:    acpi_ut_add_reference
 600  *
 601  * PARAMETERS:  *Object        - Object whose reference count is to be
 602  *                                  incremented
 603  *
 604  * RETURN:      None
 605  *
 606  * DESCRIPTION: Add one reference to an ACPI object
 607  *
 608  ******************************************************************************/
 609
 610 void
 611 acpi_ut_add_reference (
 612         union acpi_operand_object       *object)
 613 {
 614
 615         ACPI_FUNCTION_TRACE_PTR ("ut_add_reference", object);
 616
 617
 618         /* Ensure that we have a valid object */
 619
 620         if (!acpi_ut_valid_internal_object (object)) {
 621                 return_VOID;
 622         }
 623
 624         /* Increment the reference count */
 625
 626         (void) acpi_ut_update_object_reference (object, REF_INCREMENT);
 627         return_VOID;
 628 }
 629
 630
 631 /*******************************************************************************
 632  *
 633  * FUNCTION:    acpi_ut_remove_reference
 634  *
 635  * PARAMETERS:  *Object        - Object whose ref count will be decremented
 636  *
 637  * RETURN:      None
 638  *
 639  * DESCRIPTION: Decrement the reference count of an ACPI internal object
 640  *
 641  ******************************************************************************/
 642
 643 void
 644 acpi_ut_remove_reference (
 645         union acpi_operand_object       *object)
 646 {
 647
 648         ACPI_FUNCTION_TRACE_PTR ("ut_remove_reference", object);
 649
 650
 651         /*
 652          * Allow a NULL pointer to be passed in, just ignore it.  This saves
 653          * each caller from having to check.  Also, ignore NS nodes.
 654          *
 655          */
 656         if (!object ||
 657                 (ACPI_GET_DESCRIPTOR_TYPE (object) == ACPI_DESC_TYPE_NAMED)) {
 658                 return_VOID;
 659         }
 660
 661         /* Ensure that we have a valid object */
 662
 663         if (!acpi_ut_valid_internal_object (object)) {
 664                 return_VOID;
 665         }
 666
 667         ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS, "Obj %p Refs=%X\n",
 668                         object, object->common.reference_count));
 669
 670         /*
 671          * Decrement the reference count, and only actually delete the object
 672          * if the reference count becomes 0.  (Must also decrement the ref count
 673          * of all subobjects!)
 674          */
 675         (void) acpi_ut_update_object_reference (object, REF_DECREMENT);
 676         return_VOID;
 677 }
 678
 679