git.oblomov.eu Git - linux-2.6/blob - 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 #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                 /*
 139                  * These objects have a possible list of notify handlers.
 140                  * Device object also may have a GPE block.
 141                  */
 142         case ACPI_TYPE_DEVICE:
 143
 144                 if (object->device.gpe_block) {
 145                         (void)acpi_ev_delete_gpe_block(object->device.
 146                                                        gpe_block);
 147                 }
 148
 149                 /*lint -fallthrough */
 150
 151         case ACPI_TYPE_PROCESSOR:
 152         case ACPI_TYPE_THERMAL:
 153
 154                 /* Walk the notify handler list for this object */
 155
 156                 handler_desc = object->common_notify.handler;
 157                 while (handler_desc) {
 158                         next_desc = handler_desc->address_space.next;
 159                         acpi_ut_remove_reference(handler_desc);
 160                         handler_desc = next_desc;
 161                 }
 162                 break;
 163
 164         case ACPI_TYPE_MUTEX:
 165
 166                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 167                                   "***** Mutex %p, OS Mutex %p\n",
 168                                   object, object->mutex.os_mutex));
 169
 170                 if (object == acpi_gbl_global_lock_mutex) {
 171
 172                         /* Global Lock has extra semaphore */
 173
 174                         (void)
 175                             acpi_os_delete_semaphore
 176                             (acpi_gbl_global_lock_semaphore);
 177                         acpi_gbl_global_lock_semaphore = NULL;
 178
 179                         acpi_os_delete_mutex(object->mutex.os_mutex);
 180                         acpi_gbl_global_lock_mutex = NULL;
 181                 } else {
 182                         acpi_ex_unlink_mutex(object);
 183                         acpi_os_delete_mutex(object->mutex.os_mutex);
 184                 }
 185                 break;
 186
 187         case ACPI_TYPE_EVENT:
 188
 189                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 190                                   "***** Event %p, OS Semaphore %p\n",
 191                                   object, object->event.os_semaphore));
 192
 193                 (void)acpi_os_delete_semaphore(object->event.os_semaphore);
 194                 object->event.os_semaphore = NULL;
 195                 break;
 196
 197         case ACPI_TYPE_METHOD:
 198
 199                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 200                                   "***** Method %p\n", object));
 201
 202                 /* Delete the method mutex if it exists */
 203
 204                 if (object->method.mutex) {
 205                         acpi_os_delete_mutex(object->method.mutex->mutex.
 206                                              os_mutex);
 207                         acpi_ut_delete_object_desc(object->method.mutex);
 208                         object->method.mutex = NULL;
 209                 }
 210                 break;
 211
 212         case ACPI_TYPE_REGION:
 213
 214                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 215                                   "***** Region %p\n", object));
 216
 217                 second_desc = acpi_ns_get_secondary_object(object);
 218                 if (second_desc) {
 219                         /*
 220                          * Free the region_context if and only if the handler is one of the
 221                          * default handlers -- and therefore, we created the context object
 222                          * locally, it was not created by an external caller.
 223                          */
 224                         handler_desc = object->region.handler;
 225                         if (handler_desc) {
 226                                 if (handler_desc->address_space.handler_flags &
 227                                     ACPI_ADDR_HANDLER_DEFAULT_INSTALLED) {
 228
 229                                         /* Deactivate region and free region context */
 230
 231                                         if (handler_desc->address_space.setup) {
 232                                                 (void)handler_desc->
 233                                                     address_space.setup(object,
 234                                                                         ACPI_REGION_DEACTIVATE,
 235                                                                         handler_desc->
 236                                                                         address_space.
 237                                                                         context,
 238                                                                         &second_desc->
 239                                                                         extra.
 240                                                                         region_context);
 241                                         }
 242                                 }
 243
 244                                 acpi_ut_remove_reference(handler_desc);
 245                         }
 246
 247                         /* Now we can free the Extra object */
 248
 249                         acpi_ut_delete_object_desc(second_desc);
 250                 }
 251                 break;
 252
 253         case ACPI_TYPE_BUFFER_FIELD:
 254
 255                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 256                                   "***** Buffer Field %p\n", object));
 257
 258                 second_desc = acpi_ns_get_secondary_object(object);
 259                 if (second_desc) {
 260                         acpi_ut_delete_object_desc(second_desc);
 261                 }
 262                 break;
 263
 264         case ACPI_TYPE_LOCAL_BANK_FIELD:
 265
 266                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 267                                   "***** Bank Field %p\n", object));
 268
 269                 second_desc = acpi_ns_get_secondary_object(object);
 270                 if (second_desc) {
 271                         acpi_ut_delete_object_desc(second_desc);
 272                 }
 273                 break;
 274
 275         default:
 276                 break;
 277         }
 278
 279         /* Free any allocated memory (pointer within the object) found above */
 280
 281         if (obj_pointer) {
 282                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 283                                   "Deleting Object Subptr %p\n", obj_pointer));
 284                 ACPI_FREE(obj_pointer);
 285         }
 286
 287         /* Now the object can be safely deleted */
 288
 289         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS, "Deleting Object %p [%s]\n",
 290                           object, acpi_ut_get_object_type_name(object)));
 291
 292         acpi_ut_delete_object_desc(object);
 293         return_VOID;
 294 }
 295
 296 /*******************************************************************************
 297  *
 298  * FUNCTION:    acpi_ut_delete_internal_object_list
 299  *
 300  * PARAMETERS:  obj_list        - Pointer to the list to be deleted
 301  *
 302  * RETURN:      None
 303  *
 304  * DESCRIPTION: This function deletes an internal object list, including both
 305  *              simple objects and package objects
 306  *
 307  ******************************************************************************/
 308
 309 void acpi_ut_delete_internal_object_list(union acpi_operand_object **obj_list)
 310 {
 311         union acpi_operand_object **internal_obj;
 312
 313         ACPI_FUNCTION_TRACE(ut_delete_internal_object_list);
 314
 315         /* Walk the null-terminated internal list */
 316
 317         for (internal_obj = obj_list; *internal_obj; internal_obj++) {
 318                 acpi_ut_remove_reference(*internal_obj);
 319         }
 320
 321         /* Free the combined parameter pointer list and object array */
 322
 323         ACPI_FREE(obj_list);
 324         return_VOID;
 325 }
 326
 327 /*******************************************************************************
 328  *
 329  * FUNCTION:    acpi_ut_update_ref_count
 330  *
 331  * PARAMETERS:  Object          - Object whose ref count is to be updated
 332  *              Action          - What to do
 333  *
 334  * RETURN:      New ref count
 335  *
 336  * DESCRIPTION: Modify the ref count and return it.
 337  *
 338  ******************************************************************************/
 339
 340 static void
 341 acpi_ut_update_ref_count(union acpi_operand_object *object, u32 action)
 342 {
 343         u16 count;
 344         u16 new_count;
 345
 346         ACPI_FUNCTION_NAME(ut_update_ref_count);
 347
 348         if (!object) {
 349                 return;
 350         }
 351
 352         count = object->common.reference_count;
 353         new_count = count;
 354
 355         /*
 356          * Perform the reference count action (increment, decrement, force delete)
 357          */
 358         switch (action) {
 359         case REF_INCREMENT:
 360
 361                 new_count++;
 362                 object->common.reference_count = new_count;
 363
 364                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 365                                   "Obj %p Refs=%X, [Incremented]\n",
 366                                   object, new_count));
 367                 break;
 368
 369         case REF_DECREMENT:
 370
 371                 if (count < 1) {
 372                         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 373                                           "Obj %p Refs=%X, can't decrement! (Set to 0)\n",
 374                                           object, new_count));
 375
 376                         new_count = 0;
 377                 } else {
 378                         new_count--;
 379
 380                         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 381                                           "Obj %p Refs=%X, [Decremented]\n",
 382                                           object, new_count));
 383                 }
 384
 385                 if (ACPI_GET_OBJECT_TYPE(object) == ACPI_TYPE_METHOD) {
 386                         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 387                                           "Method Obj %p Refs=%X, [Decremented]\n",
 388                                           object, new_count));
 389                 }
 390
 391                 object->common.reference_count = new_count;
 392                 if (new_count == 0) {
 393                         acpi_ut_delete_internal_obj(object);
 394                 }
 395                 break;
 396
 397         case REF_FORCE_DELETE:
 398
 399                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 400                                   "Obj %p Refs=%X, Force delete! (Set to 0)\n",
 401                                   object, count));
 402
 403                 new_count = 0;
 404                 object->common.reference_count = new_count;
 405                 acpi_ut_delete_internal_obj(object);
 406                 break;
 407
 408         default:
 409
 410                 ACPI_ERROR((AE_INFO, "Unknown action (%X)", action));
 411                 break;
 412         }
 413
 414         /*
 415          * Sanity check the reference count, for debug purposes only.
 416          * (A deleted object will have a huge reference count)
 417          */
 418         if (count > ACPI_MAX_REFERENCE_COUNT) {
 419                 ACPI_WARNING((AE_INFO,
 420                               "Large Reference Count (%X) in object %p", count,
 421                               object));
 422         }
 423 }
 424
 425 /*******************************************************************************
 426  *
 427  * FUNCTION:    acpi_ut_update_object_reference
 428  *
 429  * PARAMETERS:  Object              - Increment ref count for this object
 430  *                                    and all sub-objects
 431  *              Action              - Either REF_INCREMENT or REF_DECREMENT or
 432  *                                    REF_FORCE_DELETE
 433  *
 434  * RETURN:      Status
 435  *
 436  * DESCRIPTION: Increment the object reference count
 437  *
 438  * Object references are incremented when:
 439  * 1) An object is attached to a Node (namespace object)
 440  * 2) An object is copied (all subobjects must be incremented)
 441  *
 442  * Object references are decremented when:
 443  * 1) An object is detached from an Node
 444  *
 445  ******************************************************************************/
 446
 447 acpi_status
 448 acpi_ut_update_object_reference(union acpi_operand_object *object, u16 action)
 449 {
 450         acpi_status status = AE_OK;
 451         union acpi_generic_state *state_list = NULL;
 452         union acpi_operand_object *next_object = NULL;
 453         union acpi_generic_state *state;
 454         u32 i;
 455
 456         ACPI_FUNCTION_TRACE_PTR(ut_update_object_reference, object);
 457
 458         while (object) {
 459
 460                 /* Make sure that this isn't a namespace handle */
 461
 462                 if (ACPI_GET_DESCRIPTOR_TYPE(object) == ACPI_DESC_TYPE_NAMED) {
 463                         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 464                                           "Object %p is NS handle\n", object));
 465                         return_ACPI_STATUS(AE_OK);
 466                 }
 467
 468                 /*
 469                  * All sub-objects must have their reference count incremented also.
 470                  * Different object types have different subobjects.
 471                  */
 472                 switch (ACPI_GET_OBJECT_TYPE(object)) {
 473                 case ACPI_TYPE_DEVICE:
 474                 case ACPI_TYPE_PROCESSOR:
 475                 case ACPI_TYPE_POWER:
 476                 case ACPI_TYPE_THERMAL:
 477
 478                         /* Update the notify objects for these types (if present) */
 479
 480                         acpi_ut_update_ref_count(object->common_notify.
 481                                                  system_notify, action);
 482                         acpi_ut_update_ref_count(object->common_notify.
 483                                                  device_notify, action);
 484                         break;
 485
 486                 case ACPI_TYPE_PACKAGE:
 487                         /*
 488                          * We must update all the sub-objects of the package,
 489                          * each of whom may have their own sub-objects.
 490                          */
 491                         for (i = 0; i < object->package.count; i++) {
 492                                 /*
 493                                  * Push each element onto the stack for later processing.
 494                                  * Note: There can be null elements within the package,
 495                                  * these are simply ignored
 496                                  */
 497                                 status =
 498                                     acpi_ut_create_update_state_and_push
 499                                     (object->package.elements[i], action,
 500                                      &state_list);
 501                                 if (ACPI_FAILURE(status)) {
 502                                         goto error_exit;
 503                                 }
 504                         }
 505                         break;
 506
 507                 case ACPI_TYPE_BUFFER_FIELD:
 508
 509                         next_object = object->buffer_field.buffer_obj;
 510                         break;
 511
 512                 case ACPI_TYPE_LOCAL_REGION_FIELD:
 513
 514                         next_object = object->field.region_obj;
 515                         break;
 516
 517                 case ACPI_TYPE_LOCAL_BANK_FIELD:
 518
 519                         next_object = object->bank_field.bank_obj;
 520                         status =
 521                             acpi_ut_create_update_state_and_push(object->
 522                                                                  bank_field.
 523                                                                  region_obj,
 524                                                                  action,
 525                                                                  &state_list);
 526                         if (ACPI_FAILURE(status)) {
 527                                 goto error_exit;
 528                         }
 529                         break;
 530
 531                 case ACPI_TYPE_LOCAL_INDEX_FIELD:
 532
 533                         next_object = object->index_field.index_obj;
 534                         status =
 535                             acpi_ut_create_update_state_and_push(object->
 536                                                                  index_field.
 537                                                                  data_obj,
 538                                                                  action,
 539                                                                  &state_list);
 540                         if (ACPI_FAILURE(status)) {
 541                                 goto error_exit;
 542                         }
 543                         break;
 544
 545                 case ACPI_TYPE_LOCAL_REFERENCE:
 546                         /*
 547                          * The target of an Index (a package, string, or buffer) or a named
 548                          * reference must track changes to the ref count of the index or
 549                          * target object.
 550                          */
 551                         if ((object->reference.opcode == AML_INDEX_OP) ||
 552                             (object->reference.opcode == AML_INT_NAMEPATH_OP)) {
 553                                 next_object = object->reference.object;
 554                         }
 555                         break;
 556
 557                 case ACPI_TYPE_REGION:
 558                 default:
 559                         break;  /* No subobjects for all other types */
 560                 }
 561
 562                 /*
 563                  * Now we can update the count in the main object. This can only
 564                  * happen after we update the sub-objects in case this causes the
 565                  * main object to be deleted.
 566                  */
 567                 acpi_ut_update_ref_count(object, action);
 568                 object = NULL;
 569
 570                 /* Move on to the next object to be updated */
 571
 572                 if (next_object) {
 573                         object = next_object;
 574                         next_object = NULL;
 575                 } else if (state_list) {
 576                         state = acpi_ut_pop_generic_state(&state_list);
 577                         object = state->update.object;
 578                         acpi_ut_delete_generic_state(state);
 579                 }
 580         }
 581
 582         return_ACPI_STATUS(AE_OK);
 583
 584       error_exit:
 585
 586         ACPI_EXCEPTION((AE_INFO, status,
 587                         "Could not update object reference count"));
 588
 589         return_ACPI_STATUS(status);
 590 }
 591
 592 /*******************************************************************************
 593  *
 594  * FUNCTION:    acpi_ut_add_reference
 595  *
 596  * PARAMETERS:  Object          - Object whose reference count is to be
 597  *                                incremented
 598  *
 599  * RETURN:      None
 600  *
 601  * DESCRIPTION: Add one reference to an ACPI object
 602  *
 603  ******************************************************************************/
 604
 605 void acpi_ut_add_reference(union acpi_operand_object *object)
 606 {
 607
 608         ACPI_FUNCTION_TRACE_PTR(ut_add_reference, object);
 609
 610         /* Ensure that we have a valid object */
 611
 612         if (!acpi_ut_valid_internal_object(object)) {
 613                 return_VOID;
 614         }
 615
 616         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 617                           "Obj %p Current Refs=%X [To Be Incremented]\n",
 618                           object, object->common.reference_count));
 619
 620         /* Increment the reference count */
 621
 622         (void)acpi_ut_update_object_reference(object, REF_INCREMENT);
 623         return_VOID;
 624 }
 625
 626 /*******************************************************************************
 627  *
 628  * FUNCTION:    acpi_ut_remove_reference
 629  *
 630  * PARAMETERS:  Object         - Object whose ref count will be decremented
 631  *
 632  * RETURN:      None
 633  *
 634  * DESCRIPTION: Decrement the reference count of an ACPI internal object
 635  *
 636  ******************************************************************************/
 637
 638 void acpi_ut_remove_reference(union acpi_operand_object *object)
 639 {
 640
 641         ACPI_FUNCTION_TRACE_PTR(ut_remove_reference, object);
 642
 643         /*
 644          * Allow a NULL pointer to be passed in, just ignore it. This saves
 645          * each caller from having to check. Also, ignore NS nodes.
 646          *
 647          */
 648         if (!object ||
 649             (ACPI_GET_DESCRIPTOR_TYPE(object) == ACPI_DESC_TYPE_NAMED)) {
 650                 return_VOID;
 651         }
 652
 653         /* Ensure that we have a valid object */
 654
 655         if (!acpi_ut_valid_internal_object(object)) {
 656                 return_VOID;
 657         }
 658
 659         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 660                           "Obj %p Current Refs=%X [To Be Decremented]\n",
 661                           object, object->common.reference_count));
 662
 663         /*
 664          * Decrement the reference count, and only actually delete the object
 665          * if the reference count becomes 0. (Must also decrement the ref count
 666          * of all subobjects!)
 667          */
 668         (void)acpi_ut_update_object_reference(object, REF_DECREMENT);
 669         return_VOID;
 670 }