drivers/acpi/dispatcher/dswstate.c

   1 /******************************************************************************
   2  *
   3  * Module Name: dswstate - Dispatcher parse tree walk management routines
   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/acparser.h>
  46 #include <acpi/acdispat.h>
  47 #include <acpi/acnamesp.h>
  48
  49 #define _COMPONENT          ACPI_DISPATCHER
  50 ACPI_MODULE_NAME("dswstate")
  51
  52 /* Local prototypes */
  53 #ifdef ACPI_OBSOLETE_FUNCTIONS
  54 acpi_status
  55 acpi_ds_result_insert(void *object,
  56                       u32 index, struct acpi_walk_state *walk_state);
  57
  58 acpi_status acpi_ds_obj_stack_delete_all(struct acpi_walk_state *walk_state);
  59
  60 acpi_status
  61 acpi_ds_obj_stack_pop_object(union acpi_operand_object **object,
  62                              struct acpi_walk_state *walk_state);
  63
  64 void *acpi_ds_obj_stack_get_value(u32 index,
  65                                   struct acpi_walk_state *walk_state);
  66 #endif
  67
  68 #ifdef ACPI_FUTURE_USAGE
  69 /*******************************************************************************
  70  *
  71  * FUNCTION:    acpi_ds_result_remove
  72  *
  73  * PARAMETERS:  Object              - Where to return the popped object
  74  *              Index               - Where to extract the object
  75  *              walk_state          - Current Walk state
  76  *
  77  * RETURN:      Status
  78  *
  79  * DESCRIPTION: Pop an object off the bottom of this walk's result stack.  In
  80  *              other words, this is a FIFO.
  81  *
  82  ******************************************************************************/
  83
  84 acpi_status
  85 acpi_ds_result_remove(union acpi_operand_object **object,
  86                       u32 index, struct acpi_walk_state *walk_state)
  87 {
  88         union acpi_generic_state *state;
  89
  90         ACPI_FUNCTION_NAME(ds_result_remove);
  91
  92         state = walk_state->results;
  93         if (!state) {
  94                 ACPI_ERROR((AE_INFO, "No result object pushed! State=%p",
  95                             walk_state));
  96                 return (AE_NOT_EXIST);
  97         }
  98
  99         if (index >= ACPI_OBJ_MAX_OPERAND) {
 100                 ACPI_ERROR((AE_INFO,
 101                             "Index out of range: %X State=%p Num=%X",
 102                             index, walk_state, state->results.num_results));
 103         }
 104
 105         /* Check for a valid result object */
 106
 107         if (!state->results.obj_desc[index]) {
 108                 ACPI_ERROR((AE_INFO,
 109                             "Null operand! State=%p #Ops=%X, Index=%X",
 110                             walk_state, state->results.num_results, index));
 111                 return (AE_AML_NO_RETURN_VALUE);
 112         }
 113
 114         /* Remove the object */
 115
 116         state->results.num_results--;
 117
 118         *object = state->results.obj_desc[index];
 119         state->results.obj_desc[index] = NULL;
 120
 121         ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 122                           "Obj=%p [%s] Index=%X State=%p Num=%X\n",
 123                           *object,
 124                           (*object) ? acpi_ut_get_object_type_name(*object) :
 125                           "NULL", index, walk_state,
 126                           state->results.num_results));
 127
 128         return (AE_OK);
 129 }
 130 #endif                          /*  ACPI_FUTURE_USAGE  */
 131
 132 /*******************************************************************************
 133  *
 134  * FUNCTION:    acpi_ds_result_pop
 135  *
 136  * PARAMETERS:  Object              - Where to return the popped object
 137  *              walk_state          - Current Walk state
 138  *
 139  * RETURN:      Status
 140  *
 141  * DESCRIPTION: Pop an object off the bottom of this walk's result stack.  In
 142  *              other words, this is a FIFO.
 143  *
 144  ******************************************************************************/
 145
 146 acpi_status
 147 acpi_ds_result_pop(union acpi_operand_object ** object,
 148                    struct acpi_walk_state * walk_state)
 149 {
 150         acpi_native_uint index;
 151         union acpi_generic_state *state;
 152
 153         ACPI_FUNCTION_NAME(ds_result_pop);
 154
 155         state = walk_state->results;
 156         if (!state) {
 157                 return (AE_OK);
 158         }
 159
 160         if (!state->results.num_results) {
 161                 ACPI_ERROR((AE_INFO, "Result stack is empty! State=%p",
 162                             walk_state));
 163                 return (AE_AML_NO_RETURN_VALUE);
 164         }
 165
 166         /* Remove top element */
 167
 168         state->results.num_results--;
 169
 170         for (index = ACPI_OBJ_NUM_OPERANDS; index; index--) {
 171
 172                 /* Check for a valid result object */
 173
 174                 if (state->results.obj_desc[index - 1]) {
 175                         *object = state->results.obj_desc[index - 1];
 176                         state->results.obj_desc[index - 1] = NULL;
 177
 178                         ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 179                                           "Obj=%p [%s] Index=%X State=%p Num=%X\n",
 180                                           *object,
 181                                           (*object) ?
 182                                           acpi_ut_get_object_type_name(*object)
 183                                           : "NULL", (u32) index - 1, walk_state,
 184                                           state->results.num_results));
 185
 186                         return (AE_OK);
 187                 }
 188         }
 189
 190         ACPI_ERROR((AE_INFO, "No result objects! State=%p", walk_state));
 191         return (AE_AML_NO_RETURN_VALUE);
 192 }
 193
 194 /*******************************************************************************
 195  *
 196  * FUNCTION:    acpi_ds_result_pop_from_bottom
 197  *
 198  * PARAMETERS:  Object              - Where to return the popped object
 199  *              walk_state          - Current Walk state
 200  *
 201  * RETURN:      Status
 202  *
 203  * DESCRIPTION: Pop an object off the bottom of this walk's result stack.  In
 204  *              other words, this is a FIFO.
 205  *
 206  ******************************************************************************/
 207
 208 acpi_status
 209 acpi_ds_result_pop_from_bottom(union acpi_operand_object ** object,
 210                                struct acpi_walk_state * walk_state)
 211 {
 212         acpi_native_uint index;
 213         union acpi_generic_state *state;
 214
 215         ACPI_FUNCTION_NAME(ds_result_pop_from_bottom);
 216
 217         state = walk_state->results;
 218         if (!state) {
 219                 ACPI_ERROR((AE_INFO,
 220                             "No result object pushed! State=%p", walk_state));
 221                 return (AE_NOT_EXIST);
 222         }
 223
 224         if (!state->results.num_results) {
 225                 ACPI_ERROR((AE_INFO, "No result objects! State=%p",
 226                             walk_state));
 227                 return (AE_AML_NO_RETURN_VALUE);
 228         }
 229
 230         /* Remove Bottom element */
 231
 232         *object = state->results.obj_desc[0];
 233
 234         /* Push entire stack down one element */
 235
 236         for (index = 0; index < state->results.num_results; index++) {
 237                 state->results.obj_desc[index] =
 238                     state->results.obj_desc[index + 1];
 239         }
 240
 241         state->results.num_results--;
 242
 243         /* Check for a valid result object */
 244
 245         if (!*object) {
 246                 ACPI_ERROR((AE_INFO,
 247                             "Null operand! State=%p #Ops=%X Index=%X",
 248                             walk_state, state->results.num_results,
 249                             (u32) index));
 250                 return (AE_AML_NO_RETURN_VALUE);
 251         }
 252
 253         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] Results=%p State=%p\n",
 254                           *object,
 255                           (*object) ? acpi_ut_get_object_type_name(*object) :
 256                           "NULL", state, walk_state));
 257
 258         return (AE_OK);
 259 }
 260
 261 /*******************************************************************************
 262  *
 263  * FUNCTION:    acpi_ds_result_push
 264  *
 265  * PARAMETERS:  Object              - Where to return the popped object
 266  *              walk_state          - Current Walk state
 267  *
 268  * RETURN:      Status
 269  *
 270  * DESCRIPTION: Push an object onto the current result stack
 271  *
 272  ******************************************************************************/
 273
 274 acpi_status
 275 acpi_ds_result_push(union acpi_operand_object * object,
 276                     struct acpi_walk_state * walk_state)
 277 {
 278         union acpi_generic_state *state;
 279
 280         ACPI_FUNCTION_NAME(ds_result_push);
 281
 282         state = walk_state->results;
 283         if (!state) {
 284                 ACPI_ERROR((AE_INFO, "No result stack frame during push"));
 285                 return (AE_AML_INTERNAL);
 286         }
 287
 288         if (state->results.num_results == ACPI_OBJ_NUM_OPERANDS) {
 289                 ACPI_ERROR((AE_INFO,
 290                             "Result stack overflow: Obj=%p State=%p Num=%X",
 291                             object, walk_state, state->results.num_results));
 292                 return (AE_STACK_OVERFLOW);
 293         }
 294
 295         if (!object) {
 296                 ACPI_ERROR((AE_INFO,
 297                             "Null Object! Obj=%p State=%p Num=%X",
 298                             object, walk_state, state->results.num_results));
 299                 return (AE_BAD_PARAMETER);
 300         }
 301
 302         state->results.obj_desc[state->results.num_results] = object;
 303         state->results.num_results++;
 304
 305         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] State=%p Num=%X Cur=%X\n",
 306                           object,
 307                           object ?
 308                           acpi_ut_get_object_type_name((union
 309                                                         acpi_operand_object *)
 310                                                        object) : "NULL",
 311                           walk_state, state->results.num_results,
 312                           walk_state->current_result));
 313
 314         return (AE_OK);
 315 }
 316
 317 /*******************************************************************************
 318  *
 319  * FUNCTION:    acpi_ds_result_stack_push
 320  *
 321  * PARAMETERS:  walk_state          - Current Walk state
 322  *
 323  * RETURN:      Status
 324  *
 325  * DESCRIPTION: Push an object onto the walk_state result stack.
 326  *
 327  ******************************************************************************/
 328
 329 acpi_status acpi_ds_result_stack_push(struct acpi_walk_state * walk_state)
 330 {
 331         union acpi_generic_state *state;
 332
 333         ACPI_FUNCTION_NAME(ds_result_stack_push);
 334
 335         state = acpi_ut_create_generic_state();
 336         if (!state) {
 337                 return (AE_NO_MEMORY);
 338         }
 339
 340         state->common.descriptor_type = ACPI_DESC_TYPE_STATE_RESULT;
 341         acpi_ut_push_generic_state(&walk_state->results, state);
 342
 343         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Results=%p State=%p\n",
 344                           state, walk_state));
 345
 346         return (AE_OK);
 347 }
 348
 349 /*******************************************************************************
 350  *
 351  * FUNCTION:    acpi_ds_result_stack_pop
 352  *
 353  * PARAMETERS:  walk_state          - Current Walk state
 354  *
 355  * RETURN:      Status
 356  *
 357  * DESCRIPTION: Pop an object off of the walk_state result stack.
 358  *
 359  ******************************************************************************/
 360
 361 acpi_status acpi_ds_result_stack_pop(struct acpi_walk_state * walk_state)
 362 {
 363         union acpi_generic_state *state;
 364
 365         ACPI_FUNCTION_NAME(ds_result_stack_pop);
 366
 367         /* Check for stack underflow */
 368
 369         if (walk_state->results == NULL) {
 370                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Underflow - State=%p\n",
 371                                   walk_state));
 372                 return (AE_AML_NO_OPERAND);
 373         }
 374
 375         state = acpi_ut_pop_generic_state(&walk_state->results);
 376
 377         ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 378                           "Result=%p RemainingResults=%X State=%p\n",
 379                           state, state->results.num_results, walk_state));
 380
 381         acpi_ut_delete_generic_state(state);
 382
 383         return (AE_OK);
 384 }
 385
 386 /*******************************************************************************
 387  *
 388  * FUNCTION:    acpi_ds_obj_stack_push
 389  *
 390  * PARAMETERS:  Object              - Object to push
 391  *              walk_state          - Current Walk state
 392  *
 393  * RETURN:      Status
 394  *
 395  * DESCRIPTION: Push an object onto this walk's object/operand stack
 396  *
 397  ******************************************************************************/
 398
 399 acpi_status
 400 acpi_ds_obj_stack_push(void *object, struct acpi_walk_state * walk_state)
 401 {
 402         ACPI_FUNCTION_NAME(ds_obj_stack_push);
 403
 404         /* Check for stack overflow */
 405
 406         if (walk_state->num_operands >= ACPI_OBJ_NUM_OPERANDS) {
 407                 ACPI_ERROR((AE_INFO,
 408                             "Object stack overflow! Obj=%p State=%p #Ops=%X",
 409                             object, walk_state, walk_state->num_operands));
 410                 return (AE_STACK_OVERFLOW);
 411         }
 412
 413         /* Put the object onto the stack */
 414
 415         walk_state->operands[walk_state->num_operands] = object;
 416         walk_state->num_operands++;
 417
 418         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] State=%p #Ops=%X\n",
 419                           object,
 420                           acpi_ut_get_object_type_name((union
 421                                                         acpi_operand_object *)
 422                                                        object), walk_state,
 423                           walk_state->num_operands));
 424
 425         return (AE_OK);
 426 }
 427
 428 /*******************************************************************************
 429  *
 430  * FUNCTION:    acpi_ds_obj_stack_pop
 431  *
 432  * PARAMETERS:  pop_count           - Number of objects/entries to pop
 433  *              walk_state          - Current Walk state
 434  *
 435  * RETURN:      Status
 436  *
 437  * DESCRIPTION: Pop this walk's object stack.  Objects on the stack are NOT
 438  *              deleted by this routine.
 439  *
 440  ******************************************************************************/
 441
 442 acpi_status
 443 acpi_ds_obj_stack_pop(u32 pop_count, struct acpi_walk_state * walk_state)
 444 {
 445         u32 i;
 446
 447         ACPI_FUNCTION_NAME(ds_obj_stack_pop);
 448
 449         for (i = 0; i < pop_count; i++) {
 450
 451                 /* Check for stack underflow */
 452
 453                 if (walk_state->num_operands == 0) {
 454                         ACPI_ERROR((AE_INFO,
 455                                     "Object stack underflow! Count=%X State=%p #Ops=%X",
 456                                     pop_count, walk_state,
 457                                     walk_state->num_operands));
 458                         return (AE_STACK_UNDERFLOW);
 459                 }
 460
 461                 /* Just set the stack entry to null */
 462
 463                 walk_state->num_operands--;
 464                 walk_state->operands[walk_state->num_operands] = NULL;
 465         }
 466
 467         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Count=%X State=%p #Ops=%X\n",
 468                           pop_count, walk_state, walk_state->num_operands));
 469
 470         return (AE_OK);
 471 }
 472
 473 /*******************************************************************************
 474  *
 475  * FUNCTION:    acpi_ds_obj_stack_pop_and_delete
 476  *
 477  * PARAMETERS:  pop_count           - Number of objects/entries to pop
 478  *              walk_state          - Current Walk state
 479  *
 480  * RETURN:      Status
 481  *
 482  * DESCRIPTION: Pop this walk's object stack and delete each object that is
 483  *              popped off.
 484  *
 485  ******************************************************************************/
 486
 487 acpi_status
 488 acpi_ds_obj_stack_pop_and_delete(u32 pop_count,
 489                                  struct acpi_walk_state * walk_state)
 490 {
 491         u32 i;
 492         union acpi_operand_object *obj_desc;
 493
 494         ACPI_FUNCTION_NAME(ds_obj_stack_pop_and_delete);
 495
 496         for (i = 0; i < pop_count; i++) {
 497
 498                 /* Check for stack underflow */
 499
 500                 if (walk_state->num_operands == 0) {
 501                         ACPI_ERROR((AE_INFO,
 502                                     "Object stack underflow! Count=%X State=%p #Ops=%X",
 503                                     pop_count, walk_state,
 504                                     walk_state->num_operands));
 505                         return (AE_STACK_UNDERFLOW);
 506                 }
 507
 508                 /* Pop the stack and delete an object if present in this stack entry */
 509
 510                 walk_state->num_operands--;
 511                 obj_desc = walk_state->operands[walk_state->num_operands];
 512                 if (obj_desc) {
 513                         acpi_ut_remove_reference(walk_state->
 514                                                  operands[walk_state->
 515                                                           num_operands]);
 516                         walk_state->operands[walk_state->num_operands] = NULL;
 517                 }
 518         }
 519
 520         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Count=%X State=%p #Ops=%X\n",
 521                           pop_count, walk_state, walk_state->num_operands));
 522
 523         return (AE_OK);
 524 }
 525
 526 /*******************************************************************************
 527  *
 528  * FUNCTION:    acpi_ds_get_current_walk_state
 529  *
 530  * PARAMETERS:  Thread          - Get current active state for this Thread
 531  *
 532  * RETURN:      Pointer to the current walk state
 533  *
 534  * DESCRIPTION: Get the walk state that is at the head of the list (the "current"
 535  *              walk state.)
 536  *
 537  ******************************************************************************/
 538
 539 struct acpi_walk_state *acpi_ds_get_current_walk_state(struct acpi_thread_state
 540                                                        *thread)
 541 {
 542         ACPI_FUNCTION_NAME(ds_get_current_walk_state);
 543
 544         if (!thread) {
 545                 return (NULL);
 546         }
 547
 548         ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "Current WalkState %p\n",
 549                           thread->walk_state_list));
 550
 551         return (thread->walk_state_list);
 552 }
 553
 554 /*******************************************************************************
 555  *
 556  * FUNCTION:    acpi_ds_push_walk_state
 557  *
 558  * PARAMETERS:  walk_state      - State to push
 559  *              Thread          - Thread state object
 560  *
 561  * RETURN:      None
 562  *
 563  * DESCRIPTION: Place the Thread state at the head of the state list.
 564  *
 565  ******************************************************************************/
 566
 567 void
 568 acpi_ds_push_walk_state(struct acpi_walk_state *walk_state,
 569                         struct acpi_thread_state *thread)
 570 {
 571         ACPI_FUNCTION_TRACE(ds_push_walk_state);
 572
 573         walk_state->next = thread->walk_state_list;
 574         thread->walk_state_list = walk_state;
 575
 576         return_VOID;
 577 }
 578
 579 /*******************************************************************************
 580  *
 581  * FUNCTION:    acpi_ds_pop_walk_state
 582  *
 583  * PARAMETERS:  Thread      - Current thread state
 584  *
 585  * RETURN:      A walk_state object popped from the thread's stack
 586  *
 587  * DESCRIPTION: Remove and return the walkstate object that is at the head of
 588  *              the walk stack for the given walk list.  NULL indicates that
 589  *              the list is empty.
 590  *
 591  ******************************************************************************/
 592
 593 struct acpi_walk_state *acpi_ds_pop_walk_state(struct acpi_thread_state *thread)
 594 {
 595         struct acpi_walk_state *walk_state;
 596
 597         ACPI_FUNCTION_TRACE(ds_pop_walk_state);
 598
 599         walk_state = thread->walk_state_list;
 600
 601         if (walk_state) {
 602
 603                 /* Next walk state becomes the current walk state */
 604
 605                 thread->walk_state_list = walk_state->next;
 606
 607                 /*
 608                  * Don't clear the NEXT field, this serves as an indicator
 609                  * that there is a parent WALK STATE
 610                  * Do Not: walk_state->Next = NULL;
 611                  */
 612         }
 613
 614         return_PTR(walk_state);
 615 }
 616
 617 /*******************************************************************************
 618  *
 619  * FUNCTION:    acpi_ds_create_walk_state
 620  *
 621  * PARAMETERS:  owner_id        - ID for object creation
 622  *              Origin          - Starting point for this walk
 623  *              method_desc     - Method object
 624  *              Thread          - Current thread state
 625  *
 626  * RETURN:      Pointer to the new walk state.
 627  *
 628  * DESCRIPTION: Allocate and initialize a new walk state.  The current walk
 629  *              state is set to this new state.
 630  *
 631  ******************************************************************************/
 632
 633 struct acpi_walk_state *acpi_ds_create_walk_state(acpi_owner_id owner_id, union acpi_parse_object
 634                                                   *origin, union acpi_operand_object
 635                                                   *method_desc, struct acpi_thread_state
 636                                                   *thread)
 637 {
 638         struct acpi_walk_state *walk_state;
 639         acpi_status status;
 640
 641         ACPI_FUNCTION_TRACE(ds_create_walk_state);
 642
 643         walk_state = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_walk_state));
 644         if (!walk_state) {
 645                 return_PTR(NULL);
 646         }
 647
 648         walk_state->descriptor_type = ACPI_DESC_TYPE_WALK;
 649         walk_state->method_desc = method_desc;
 650         walk_state->owner_id = owner_id;
 651         walk_state->origin = origin;
 652         walk_state->thread = thread;
 653
 654         walk_state->parser_state.start_op = origin;
 655
 656         /* Init the method args/local */
 657
 658 #if (!defined (ACPI_NO_METHOD_EXECUTION) && !defined (ACPI_CONSTANT_EVAL_ONLY))
 659         acpi_ds_method_data_init(walk_state);
 660 #endif
 661
 662         /* Create an initial result stack entry */
 663
 664         status = acpi_ds_result_stack_push(walk_state);
 665         if (ACPI_FAILURE(status)) {
 666                 ACPI_FREE(walk_state);
 667                 return_PTR(NULL);
 668         }
 669
 670         /* Put the new state at the head of the walk list */
 671
 672         if (thread) {
 673                 acpi_ds_push_walk_state(walk_state, thread);
 674         }
 675
 676         return_PTR(walk_state);
 677 }
 678
 679 /*******************************************************************************
 680  *
 681  * FUNCTION:    acpi_ds_init_aml_walk
 682  *
 683  * PARAMETERS:  walk_state      - New state to be initialized
 684  *              Op              - Current parse op
 685  *              method_node     - Control method NS node, if any
 686  *              aml_start       - Start of AML
 687  *              aml_length      - Length of AML
 688  *              Info            - Method info block (params, etc.)
 689  *              pass_number     - 1, 2, or 3
 690  *
 691  * RETURN:      Status
 692  *
 693  * DESCRIPTION: Initialize a walk state for a pass 1 or 2 parse tree walk
 694  *
 695  ******************************************************************************/
 696
 697 acpi_status
 698 acpi_ds_init_aml_walk(struct acpi_walk_state *walk_state,
 699                       union acpi_parse_object *op,
 700                       struct acpi_namespace_node *method_node,
 701                       u8 * aml_start,
 702                       u32 aml_length,
 703                       struct acpi_evaluate_info *info, u8 pass_number)
 704 {
 705         acpi_status status;
 706         struct acpi_parse_state *parser_state = &walk_state->parser_state;
 707         union acpi_parse_object *extra_op;
 708
 709         ACPI_FUNCTION_TRACE(ds_init_aml_walk);
 710
 711         walk_state->parser_state.aml =
 712             walk_state->parser_state.aml_start = aml_start;
 713         walk_state->parser_state.aml_end =
 714             walk_state->parser_state.pkg_end = aml_start + aml_length;
 715
 716         /* The next_op of the next_walk will be the beginning of the method */
 717
 718         walk_state->next_op = NULL;
 719         walk_state->pass_number = pass_number;
 720
 721         if (info) {
 722                 if (info->parameter_type == ACPI_PARAM_GPE) {
 723                         walk_state->gpe_event_info =
 724                             ACPI_CAST_PTR(struct acpi_gpe_event_info,
 725                                           info->parameters);
 726                 } else {
 727                         walk_state->params = info->parameters;
 728                         walk_state->caller_return_desc = &info->return_object;
 729                 }
 730         }
 731
 732         status = acpi_ps_init_scope(&walk_state->parser_state, op);
 733         if (ACPI_FAILURE(status)) {
 734                 return_ACPI_STATUS(status);
 735         }
 736
 737         if (method_node) {
 738                 walk_state->parser_state.start_node = method_node;
 739                 walk_state->walk_type = ACPI_WALK_METHOD;
 740                 walk_state->method_node = method_node;
 741                 walk_state->method_desc =
 742                     acpi_ns_get_attached_object(method_node);
 743
 744                 /* Push start scope on scope stack and make it current  */
 745
 746                 status =
 747                     acpi_ds_scope_stack_push(method_node, ACPI_TYPE_METHOD,
 748                                              walk_state);
 749                 if (ACPI_FAILURE(status)) {
 750                         return_ACPI_STATUS(status);
 751                 }
 752
 753                 /* Init the method arguments */
 754
 755                 status = acpi_ds_method_data_init_args(walk_state->params,
 756                                                        ACPI_METHOD_NUM_ARGS,
 757                                                        walk_state);
 758                 if (ACPI_FAILURE(status)) {
 759                         return_ACPI_STATUS(status);
 760                 }
 761         } else {
 762                 /*
 763                  * Setup the current scope.
 764                  * Find a Named Op that has a namespace node associated with it.
 765                  * search upwards from this Op.  Current scope is the first
 766                  * Op with a namespace node.
 767                  */
 768                 extra_op = parser_state->start_op;
 769                 while (extra_op && !extra_op->common.node) {
 770                         extra_op = extra_op->common.parent;
 771                 }
 772
 773                 if (!extra_op) {
 774                         parser_state->start_node = NULL;
 775                 } else {
 776                         parser_state->start_node = extra_op->common.node;
 777                 }
 778
 779                 if (parser_state->start_node) {
 780
 781                         /* Push start scope on scope stack and make it current  */
 782
 783                         status =
 784                             acpi_ds_scope_stack_push(parser_state->start_node,
 785                                                      parser_state->start_node->
 786                                                      type, walk_state);
 787                         if (ACPI_FAILURE(status)) {
 788                                 return_ACPI_STATUS(status);
 789                         }
 790                 }
 791         }
 792
 793         status = acpi_ds_init_callbacks(walk_state, pass_number);
 794         return_ACPI_STATUS(status);
 795 }
 796
 797 /*******************************************************************************
 798  *
 799  * FUNCTION:    acpi_ds_delete_walk_state
 800  *
 801  * PARAMETERS:  walk_state      - State to delete
 802  *
 803  * RETURN:      Status
 804  *
 805  * DESCRIPTION: Delete a walk state including all internal data structures
 806  *
 807  ******************************************************************************/
 808
 809 void acpi_ds_delete_walk_state(struct acpi_walk_state *walk_state)
 810 {
 811         union acpi_generic_state *state;
 812
 813         ACPI_FUNCTION_TRACE_PTR(ds_delete_walk_state, walk_state);
 814
 815         if (!walk_state) {
 816                 return;
 817         }
 818
 819         if (walk_state->descriptor_type != ACPI_DESC_TYPE_WALK) {
 820                 ACPI_ERROR((AE_INFO, "%p is not a valid walk state",
 821                             walk_state));
 822                 return;
 823         }
 824
 825         /* There should not be any open scopes */
 826
 827         if (walk_state->parser_state.scope) {
 828                 ACPI_ERROR((AE_INFO, "%p walk still has a scope list",
 829                             walk_state));
 830                 acpi_ps_cleanup_scope(&walk_state->parser_state);
 831         }
 832
 833         /* Always must free any linked control states */
 834
 835         while (walk_state->control_state) {
 836                 state = walk_state->control_state;
 837                 walk_state->control_state = state->common.next;
 838
 839                 acpi_ut_delete_generic_state(state);
 840         }
 841
 842         /* Always must free any linked parse states */
 843
 844         while (walk_state->scope_info) {
 845                 state = walk_state->scope_info;
 846                 walk_state->scope_info = state->common.next;
 847
 848                 acpi_ut_delete_generic_state(state);
 849         }
 850
 851         /* Always must free any stacked result states */
 852
 853         while (walk_state->results) {
 854                 state = walk_state->results;
 855                 walk_state->results = state->common.next;
 856
 857                 acpi_ut_delete_generic_state(state);
 858         }
 859
 860         ACPI_FREE(walk_state);
 861         return_VOID;
 862 }
 863
 864 #ifdef ACPI_OBSOLETE_FUNCTIONS
 865 /*******************************************************************************
 866  *
 867  * FUNCTION:    acpi_ds_result_insert
 868  *
 869  * PARAMETERS:  Object              - Object to push
 870  *              Index               - Where to insert the object
 871  *              walk_state          - Current Walk state
 872  *
 873  * RETURN:      Status
 874  *
 875  * DESCRIPTION: Insert an object onto this walk's result stack
 876  *
 877  ******************************************************************************/
 878
 879 acpi_status
 880 acpi_ds_result_insert(void *object,
 881                       u32 index, struct acpi_walk_state *walk_state)
 882 {
 883         union acpi_generic_state *state;
 884
 885         ACPI_FUNCTION_NAME(ds_result_insert);
 886
 887         state = walk_state->results;
 888         if (!state) {
 889                 ACPI_ERROR((AE_INFO, "No result object pushed! State=%p",
 890                             walk_state));
 891                 return (AE_NOT_EXIST);
 892         }
 893
 894         if (index >= ACPI_OBJ_NUM_OPERANDS) {
 895                 ACPI_ERROR((AE_INFO,
 896                             "Index out of range: %X Obj=%p State=%p Num=%X",
 897                             index, object, walk_state,
 898                             state->results.num_results));
 899                 return (AE_BAD_PARAMETER);
 900         }
 901
 902         if (!object) {
 903                 ACPI_ERROR((AE_INFO,
 904                             "Null Object! Index=%X Obj=%p State=%p Num=%X",
 905                             index, object, walk_state,
 906                             state->results.num_results));
 907                 return (AE_BAD_PARAMETER);
 908         }
 909
 910         state->results.obj_desc[index] = object;
 911         state->results.num_results++;
 912
 913         ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 914                           "Obj=%p [%s] State=%p Num=%X Cur=%X\n",
 915                           object,
 916                           object ?
 917                           acpi_ut_get_object_type_name((union
 918                                                         acpi_operand_object *)
 919                                                        object) : "NULL",
 920                           walk_state, state->results.num_results,
 921                           walk_state->current_result));
 922
 923         return (AE_OK);
 924 }
 925
 926 /*******************************************************************************
 927  *
 928  * FUNCTION:    acpi_ds_obj_stack_delete_all
 929  *
 930  * PARAMETERS:  walk_state          - Current Walk state
 931  *
 932  * RETURN:      Status
 933  *
 934  * DESCRIPTION: Clear the object stack by deleting all objects that are on it.
 935  *              Should be used with great care, if at all!
 936  *
 937  ******************************************************************************/
 938
 939 acpi_status acpi_ds_obj_stack_delete_all(struct acpi_walk_state * walk_state)
 940 {
 941         u32 i;
 942
 943         ACPI_FUNCTION_TRACE_PTR(ds_obj_stack_delete_all, walk_state);
 944
 945         /* The stack size is configurable, but fixed */
 946
 947         for (i = 0; i < ACPI_OBJ_NUM_OPERANDS; i++) {
 948                 if (walk_state->operands[i]) {
 949                         acpi_ut_remove_reference(walk_state->operands[i]);
 950                         walk_state->operands[i] = NULL;
 951                 }
 952         }
 953
 954         return_ACPI_STATUS(AE_OK);
 955 }
 956
 957 /*******************************************************************************
 958  *
 959  * FUNCTION:    acpi_ds_obj_stack_pop_object
 960  *
 961  * PARAMETERS:  Object              - Where to return the popped object
 962  *              walk_state          - Current Walk state
 963  *
 964  * RETURN:      Status
 965  *
 966  * DESCRIPTION: Pop this walk's object stack.  Objects on the stack are NOT
 967  *              deleted by this routine.
 968  *
 969  ******************************************************************************/
 970
 971 acpi_status
 972 acpi_ds_obj_stack_pop_object(union acpi_operand_object **object,
 973                              struct acpi_walk_state *walk_state)
 974 {
 975         ACPI_FUNCTION_NAME(ds_obj_stack_pop_object);
 976
 977         /* Check for stack underflow */
 978
 979         if (walk_state->num_operands == 0) {
 980                 ACPI_ERROR((AE_INFO,
 981                             "Missing operand/stack empty! State=%p #Ops=%X",
 982                             walk_state, walk_state->num_operands));
 983                 *object = NULL;
 984                 return (AE_AML_NO_OPERAND);
 985         }
 986
 987         /* Pop the stack */
 988
 989         walk_state->num_operands--;
 990
 991         /* Check for a valid operand */
 992
 993         if (!walk_state->operands[walk_state->num_operands]) {
 994                 ACPI_ERROR((AE_INFO,
 995                             "Null operand! State=%p #Ops=%X",
 996                             walk_state, walk_state->num_operands));
 997                 *object = NULL;
 998                 return (AE_AML_NO_OPERAND);
 999         }
1000
1001         /* Get operand and set stack entry to null */
1002
1003         *object = walk_state->operands[walk_state->num_operands];
1004         walk_state->operands[walk_state->num_operands] = NULL;
1005
1006         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] State=%p #Ops=%X\n",
1007                           *object, acpi_ut_get_object_type_name(*object),
1008                           walk_state, walk_state->num_operands));
1009
1010         return (AE_OK);
1011 }
1012
1013 /*******************************************************************************
1014  *
1015  * FUNCTION:    acpi_ds_obj_stack_get_value
1016  *
1017  * PARAMETERS:  Index               - Stack index whose value is desired.  Based
1018  *                                    on the top of the stack (index=0 == top)
1019  *              walk_state          - Current Walk state
1020  *
1021  * RETURN:      Pointer to the requested operand
1022  *
1023  * DESCRIPTION: Retrieve an object from this walk's operand stack.  Index must
1024  *              be within the range of the current stack pointer.
1025  *
1026  ******************************************************************************/
1027
1028 void *acpi_ds_obj_stack_get_value(u32 index, struct acpi_walk_state *walk_state)
1029 {
1030
1031         ACPI_FUNCTION_TRACE_PTR(ds_obj_stack_get_value, walk_state);
1032
1033         /* Can't do it if the stack is empty */
1034
1035         if (walk_state->num_operands == 0) {
1036                 return_PTR(NULL);
1037         }
1038
1039         /* or if the index is past the top of the stack */
1040
1041         if (index > (walk_state->num_operands - (u32) 1)) {
1042                 return_PTR(NULL);
1043         }
1044
1045         return_PTR(walk_state->
1046                    operands[(acpi_native_uint) (walk_state->num_operands - 1) -
1047                             index]);
1048 }
1049 #endif