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