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 - 2005, R. Byron Moore
   9  * All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions, and the following disclaimer,
  16  *    without modification.
  17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  18  *    substantially similar to the "NO WARRANTY" disclaimer below
  19  *    ("Disclaimer") and any redistribution must be conditioned upon
  20  *    including a substantially similar Disclaimer requirement for further
  21  *    binary redistribution.
  22  * 3. Neither the names of the above-listed copyright holders nor the names
  23  *    of any contributors may be used to endorse or promote products derived
  24  *    from this software without specific prior written permission.
  25  *
  26  * Alternatively, this software may be distributed under the terms of the
  27  * GNU General Public License ("GPL") version 2 as published by the Free
  28  * Software Foundation.
  29  *
  30  * NO WARRANTY
  31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  41  * POSSIBILITY OF SUCH DAMAGES.
  42  */
  43
  44
  45 #include <acpi/acpi.h>
  46 #include <acpi/acparser.h>
  47 #include <acpi/acdispat.h>
  48 #include <acpi/acnamesp.h>
  49
  50 #define _COMPONENT          ACPI_DISPATCHER
  51          ACPI_MODULE_NAME    ("dswstate")
  52
  53
  54 #ifdef ACPI_FUTURE_USAGE
  55
  56 /*******************************************************************************
  57  *
  58  * FUNCTION:    acpi_ds_result_insert
  59  *
  60  * PARAMETERS:  Object              - Object to push
  61  *              Index               - Where to insert the object
  62  *              walk_state          - Current Walk state
  63  *
  64  * RETURN:      Status
  65  *
  66  * DESCRIPTION: Insert an object onto this walk's result stack
  67  *
  68  ******************************************************************************/
  69
  70 acpi_status
  71 acpi_ds_result_insert (
  72         void                            *object,
  73         u32                             index,
  74         struct acpi_walk_state          *walk_state)
  75 {
  76         union acpi_generic_state        *state;
  77
  78
  79         ACPI_FUNCTION_NAME ("ds_result_insert");
  80
  81
  82         state = walk_state->results;
  83         if (!state) {
  84                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "No result object pushed! State=%p\n",
  85                         walk_state));
  86                 return (AE_NOT_EXIST);
  87         }
  88
  89         if (index >= ACPI_OBJ_NUM_OPERANDS) {
  90                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
  91                         "Index out of range: %X Obj=%p State=%p Num=%X\n",
  92                         index, object, walk_state, state->results.num_results));
  93                 return (AE_BAD_PARAMETER);
  94         }
  95
  96         if (!object) {
  97                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
  98                         "Null Object! Index=%X Obj=%p State=%p Num=%X\n",
  99                         index, object, walk_state, state->results.num_results));
 100                 return (AE_BAD_PARAMETER);
 101         }
 102
 103         state->results.obj_desc [index] = object;
 104         state->results.num_results++;
 105
 106         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
 107                 "Obj=%p [%s] State=%p Num=%X Cur=%X\n",
 108                 object, object ? acpi_ut_get_object_type_name ((union acpi_operand_object *) object) : "NULL",
 109                 walk_state, state->results.num_results, walk_state->current_result));
 110
 111         return (AE_OK);
 112 }
 113
 114
 115 /*******************************************************************************
 116  *
 117  * FUNCTION:    acpi_ds_result_remove
 118  *
 119  * PARAMETERS:  Object              - Where to return the popped object
 120  *              Index               - Where to extract the object
 121  *              walk_state          - Current Walk state
 122  *
 123  * RETURN:      Status
 124  *
 125  * DESCRIPTION: Pop an object off the bottom of this walk's result stack.  In
 126  *              other words, this is a FIFO.
 127  *
 128  ******************************************************************************/
 129
 130 acpi_status
 131 acpi_ds_result_remove (
 132         union acpi_operand_object       **object,
 133         u32                             index,
 134         struct acpi_walk_state          *walk_state)
 135 {
 136         union acpi_generic_state        *state;
 137
 138
 139         ACPI_FUNCTION_NAME ("ds_result_remove");
 140
 141
 142         state = walk_state->results;
 143         if (!state) {
 144                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "No result object pushed! State=%p\n",
 145                         walk_state));
 146                 return (AE_NOT_EXIST);
 147         }
 148
 149         if (index >= ACPI_OBJ_MAX_OPERAND) {
 150                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
 151                         "Index out of range: %X State=%p Num=%X\n",
 152                         index, walk_state, state->results.num_results));
 153         }
 154
 155         /* Check for a valid result object */
 156
 157         if (!state->results.obj_desc [index]) {
 158                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
 159                         "Null operand! State=%p #Ops=%X, Index=%X\n",
 160                         walk_state, state->results.num_results, index));
 161                 return (AE_AML_NO_RETURN_VALUE);
 162         }
 163
 164         /* Remove the object */
 165
 166         state->results.num_results--;
 167
 168         *object = state->results.obj_desc [index];
 169         state->results.obj_desc [index] = NULL;
 170
 171         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
 172                 "Obj=%p [%s] Index=%X State=%p Num=%X\n",
 173                 *object, (*object) ? acpi_ut_get_object_type_name (*object) : "NULL",
 174                 index, walk_state, state->results.num_results));
 175
 176         return (AE_OK);
 177 }
 178
 179 #endif  /*  ACPI_FUTURE_USAGE  */
 180
 181
 182 /*******************************************************************************
 183  *
 184  * FUNCTION:    acpi_ds_result_pop
 185  *
 186  * PARAMETERS:  Object              - Where to return the popped object
 187  *              walk_state          - Current Walk state
 188  *
 189  * RETURN:      Status
 190  *
 191  * DESCRIPTION: Pop an object off the bottom of this walk's result stack.  In
 192  *              other words, this is a FIFO.
 193  *
 194  ******************************************************************************/
 195
 196 acpi_status
 197 acpi_ds_result_pop (
 198         union acpi_operand_object       **object,
 199         struct acpi_walk_state          *walk_state)
 200 {
 201         acpi_native_uint                index;
 202         union acpi_generic_state        *state;
 203
 204
 205         ACPI_FUNCTION_NAME ("ds_result_pop");
 206
 207
 208         state = walk_state->results;
 209         if (!state) {
 210                 return (AE_OK);
 211         }
 212
 213         if (!state->results.num_results) {
 214                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Result stack is empty! State=%p\n",
 215                         walk_state));
 216                 return (AE_AML_NO_RETURN_VALUE);
 217         }
 218
 219         /* Remove top element */
 220
 221         state->results.num_results--;
 222
 223         for (index = ACPI_OBJ_NUM_OPERANDS; index; index--) {
 224                 /* Check for a valid result object */
 225
 226                 if (state->results.obj_desc [index -1]) {
 227                         *object = state->results.obj_desc [index -1];
 228                         state->results.obj_desc [index -1] = NULL;
 229
 230                         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Obj=%p [%s] Index=%X State=%p Num=%X\n",
 231                                 *object, (*object) ? acpi_ut_get_object_type_name (*object) : "NULL",
 232                                 (u32) index -1, walk_state, state->results.num_results));
 233
 234                         return (AE_OK);
 235                 }
 236         }
 237
 238         ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "No result objects! State=%p\n", walk_state));
 239         return (AE_AML_NO_RETURN_VALUE);
 240 }
 241
 242
 243 /*******************************************************************************
 244  *
 245  * FUNCTION:    acpi_ds_result_pop_from_bottom
 246  *
 247  * PARAMETERS:  Object              - Where to return the popped object
 248  *              walk_state          - Current Walk state
 249  *
 250  * RETURN:      Status
 251  *
 252  * DESCRIPTION: Pop an object off the bottom of this walk's result stack.  In
 253  *              other words, this is a FIFO.
 254  *
 255  ******************************************************************************/
 256
 257 acpi_status
 258 acpi_ds_result_pop_from_bottom (
 259         union acpi_operand_object       **object,
 260         struct acpi_walk_state          *walk_state)
 261 {
 262         acpi_native_uint                index;
 263         union acpi_generic_state        *state;
 264
 265
 266         ACPI_FUNCTION_NAME ("ds_result_pop_from_bottom");
 267
 268
 269         state = walk_state->results;
 270         if (!state) {
 271                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
 272                         "Warning: No result object pushed! State=%p\n", walk_state));
 273                 return (AE_NOT_EXIST);
 274         }
 275
 276         if (!state->results.num_results) {
 277                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "No result objects! State=%p\n", walk_state));
 278                 return (AE_AML_NO_RETURN_VALUE);
 279         }
 280
 281         /* Remove Bottom element */
 282
 283         *object = state->results.obj_desc [0];
 284
 285         /* Push entire stack down one element */
 286
 287         for (index = 0; index < state->results.num_results; index++) {
 288                 state->results.obj_desc [index] = state->results.obj_desc [index + 1];
 289         }
 290
 291         state->results.num_results--;
 292
 293         /* Check for a valid result object */
 294
 295         if (!*object) {
 296                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Null operand! State=%p #Ops=%X, Index=%X\n",
 297                         walk_state, state->results.num_results, (u32) index));
 298                 return (AE_AML_NO_RETURN_VALUE);
 299         }
 300
 301         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Obj=%p [%s], Results=%p State=%p\n",
 302                 *object, (*object) ? acpi_ut_get_object_type_name (*object) : "NULL",
 303                 state, walk_state));
 304
 305         return (AE_OK);
 306 }
 307
 308
 309 /*******************************************************************************
 310  *
 311  * FUNCTION:    acpi_ds_result_push
 312  *
 313  * PARAMETERS:  Object              - Where to return the popped object
 314  *              walk_state          - Current Walk state
 315  *
 316  * RETURN:      Status
 317  *
 318  * DESCRIPTION: Push an object onto the current result stack
 319  *
 320  ******************************************************************************/
 321
 322 acpi_status
 323 acpi_ds_result_push (
 324         union acpi_operand_object       *object,
 325         struct acpi_walk_state          *walk_state)
 326 {
 327         union acpi_generic_state        *state;
 328
 329
 330         ACPI_FUNCTION_NAME ("ds_result_push");
 331
 332
 333         state = walk_state->results;
 334         if (!state) {
 335                 ACPI_REPORT_ERROR (("No result stack frame during push\n"));
 336                 return (AE_AML_INTERNAL);
 337         }
 338
 339         if (state->results.num_results == ACPI_OBJ_NUM_OPERANDS) {
 340                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
 341                         "Result stack overflow: Obj=%p State=%p Num=%X\n",
 342                         object, walk_state, state->results.num_results));
 343                 return (AE_STACK_OVERFLOW);
 344         }
 345
 346         if (!object) {
 347                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Null Object! Obj=%p State=%p Num=%X\n",
 348                         object, walk_state, state->results.num_results));
 349                 return (AE_BAD_PARAMETER);
 350         }
 351
 352         state->results.obj_desc [state->results.num_results] = object;
 353         state->results.num_results++;
 354
 355         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Obj=%p [%s] State=%p Num=%X Cur=%X\n",
 356                 object, object ? acpi_ut_get_object_type_name ((union acpi_operand_object *) object) : "NULL",
 357                 walk_state, state->results.num_results, walk_state->current_result));
 358
 359         return (AE_OK);
 360 }
 361
 362
 363 /*******************************************************************************
 364  *
 365  * FUNCTION:    acpi_ds_result_stack_push
 366  *
 367  * PARAMETERS:  walk_state          - Current Walk state
 368  *
 369  * RETURN:      Status
 370  *
 371  * DESCRIPTION: Push an object onto the walk_state result stack.
 372  *
 373  ******************************************************************************/
 374
 375 acpi_status
 376 acpi_ds_result_stack_push (
 377         struct acpi_walk_state          *walk_state)
 378 {
 379         union acpi_generic_state        *state;
 380
 381         ACPI_FUNCTION_NAME ("ds_result_stack_push");
 382
 383
 384         state = acpi_ut_create_generic_state ();
 385         if (!state) {
 386                 return (AE_NO_MEMORY);
 387         }
 388
 389         state->common.data_type = ACPI_DESC_TYPE_STATE_RESULT;
 390         acpi_ut_push_generic_state (&walk_state->results, state);
 391
 392         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Results=%p State=%p\n",
 393                 state, walk_state));
 394
 395         return (AE_OK);
 396 }
 397
 398
 399 /*******************************************************************************
 400  *
 401  * FUNCTION:    acpi_ds_result_stack_pop
 402  *
 403  * PARAMETERS:  walk_state          - Current Walk state
 404  *
 405  * RETURN:      Status
 406  *
 407  * DESCRIPTION: Pop an object off of the walk_state result stack.
 408  *
 409  ******************************************************************************/
 410
 411 acpi_status
 412 acpi_ds_result_stack_pop (
 413         struct acpi_walk_state          *walk_state)
 414 {
 415         union acpi_generic_state        *state;
 416
 417         ACPI_FUNCTION_NAME ("ds_result_stack_pop");
 418
 419
 420         /* Check for stack underflow */
 421
 422         if (walk_state->results == NULL) {
 423                 ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Underflow - State=%p\n",
 424                         walk_state));
 425                 return (AE_AML_NO_OPERAND);
 426         }
 427
 428         state = acpi_ut_pop_generic_state (&walk_state->results);
 429
 430         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
 431                 "Result=%p remaining_results=%X State=%p\n",
 432                 state, state->results.num_results, walk_state));
 433
 434         acpi_ut_delete_generic_state (state);
 435
 436         return (AE_OK);
 437 }
 438
 439
 440 /*******************************************************************************
 441  *
 442  * FUNCTION:    acpi_ds_obj_stack_delete_all
 443  *
 444  * PARAMETERS:  walk_state          - Current Walk state
 445  *
 446  * RETURN:      Status
 447  *
 448  * DESCRIPTION: Clear the object stack by deleting all objects that are on it.
 449  *              Should be used with great care, if at all!
 450  *
 451  ******************************************************************************/
 452 #ifdef ACPI_FUTURE_USAGE
 453 acpi_status
 454 acpi_ds_obj_stack_delete_all (
 455         struct acpi_walk_state          *walk_state)
 456 {
 457         u32                             i;
 458
 459
 460         ACPI_FUNCTION_TRACE_PTR ("ds_obj_stack_delete_all", walk_state);
 461
 462
 463         /* The stack size is configurable, but fixed */
 464
 465         for (i = 0; i < ACPI_OBJ_NUM_OPERANDS; i++) {
 466                 if (walk_state->operands[i]) {
 467                         acpi_ut_remove_reference (walk_state->operands[i]);
 468                         walk_state->operands[i] = NULL;
 469                 }
 470         }
 471
 472         return_ACPI_STATUS (AE_OK);
 473 }
 474 #endif  /*  ACPI_FUTURE_USAGE  */
 475
 476
 477 /*******************************************************************************
 478  *
 479  * FUNCTION:    acpi_ds_obj_stack_push
 480  *
 481  * PARAMETERS:  Object              - Object to push
 482  *              walk_state          - Current Walk state
 483  *
 484  * RETURN:      Status
 485  *
 486  * DESCRIPTION: Push an object onto this walk's object/operand stack
 487  *
 488  ******************************************************************************/
 489
 490 acpi_status
 491 acpi_ds_obj_stack_push (
 492         void                            *object,
 493         struct acpi_walk_state          *walk_state)
 494 {
 495         ACPI_FUNCTION_NAME ("ds_obj_stack_push");
 496
 497
 498         /* Check for stack overflow */
 499
 500         if (walk_state->num_operands >= ACPI_OBJ_NUM_OPERANDS) {
 501                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
 502                         "overflow! Obj=%p State=%p #Ops=%X\n",
 503                         object, walk_state, walk_state->num_operands));
 504                 return (AE_STACK_OVERFLOW);
 505         }
 506
 507         /* Put the object onto the stack */
 508
 509         walk_state->operands [walk_state->num_operands] = object;
 510         walk_state->num_operands++;
 511
 512         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Obj=%p [%s] State=%p #Ops=%X\n",
 513                           object, acpi_ut_get_object_type_name ((union acpi_operand_object *) object),
 514                           walk_state, walk_state->num_operands));
 515
 516         return (AE_OK);
 517 }
 518
 519
 520 #if 0
 521 /*******************************************************************************
 522  *
 523  * FUNCTION:    acpi_ds_obj_stack_pop_object
 524  *
 525  * PARAMETERS:  pop_count           - Number of objects/entries to pop
 526  *              walk_state          - Current Walk state
 527  *
 528  * RETURN:      Status
 529  *
 530  * DESCRIPTION: Pop this walk's object stack.  Objects on the stack are NOT
 531  *              deleted by this routine.
 532  *
 533  ******************************************************************************/
 534
 535 acpi_status
 536 acpi_ds_obj_stack_pop_object (
 537         union acpi_operand_object       **object,
 538         struct acpi_walk_state          *walk_state)
 539 {
 540         ACPI_FUNCTION_NAME ("ds_obj_stack_pop_object");
 541
 542
 543         /* Check for stack underflow */
 544
 545         if (walk_state->num_operands == 0) {
 546                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
 547                         "Missing operand/stack empty! State=%p #Ops=%X\n",
 548                         walk_state, walk_state->num_operands));
 549                 *object = NULL;
 550                 return (AE_AML_NO_OPERAND);
 551         }
 552
 553         /* Pop the stack */
 554
 555         walk_state->num_operands--;
 556
 557         /* Check for a valid operand */
 558
 559         if (!walk_state->operands [walk_state->num_operands]) {
 560                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
 561                         "Null operand! State=%p #Ops=%X\n",
 562                         walk_state, walk_state->num_operands));
 563                 *object = NULL;
 564                 return (AE_AML_NO_OPERAND);
 565         }
 566
 567         /* Get operand and set stack entry to null */
 568
 569         *object = walk_state->operands [walk_state->num_operands];
 570         walk_state->operands [walk_state->num_operands] = NULL;
 571
 572         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Obj=%p [%s] State=%p #Ops=%X\n",
 573                           *object, acpi_ut_get_object_type_name (*object),
 574                           walk_state, walk_state->num_operands));
 575
 576         return (AE_OK);
 577 }
 578 #endif
 579
 580
 581 /*******************************************************************************
 582  *
 583  * FUNCTION:    acpi_ds_obj_stack_pop
 584  *
 585  * PARAMETERS:  pop_count           - Number of objects/entries to pop
 586  *              walk_state          - Current Walk state
 587  *
 588  * RETURN:      Status
 589  *
 590  * DESCRIPTION: Pop this walk's object stack.  Objects on the stack are NOT
 591  *              deleted by this routine.
 592  *
 593  ******************************************************************************/
 594
 595 acpi_status
 596 acpi_ds_obj_stack_pop (
 597         u32                             pop_count,
 598         struct acpi_walk_state          *walk_state)
 599 {
 600         u32                             i;
 601
 602         ACPI_FUNCTION_NAME ("ds_obj_stack_pop");
 603
 604
 605         for (i = 0; i < pop_count; i++) {
 606                 /* Check for stack underflow */
 607
 608                 if (walk_state->num_operands == 0) {
 609                         ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
 610                                 "Underflow! Count=%X State=%p #Ops=%X\n",
 611                                 pop_count, walk_state, walk_state->num_operands));
 612                         return (AE_STACK_UNDERFLOW);
 613                 }
 614
 615                 /* Just set the stack entry to null */
 616
 617                 walk_state->num_operands--;
 618                 walk_state->operands [walk_state->num_operands] = NULL;
 619         }
 620
 621         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Count=%X State=%p #Ops=%X\n",
 622                           pop_count, walk_state, walk_state->num_operands));
 623
 624         return (AE_OK);
 625 }
 626
 627
 628 /*******************************************************************************
 629  *
 630  * FUNCTION:    acpi_ds_obj_stack_pop_and_delete
 631  *
 632  * PARAMETERS:  pop_count           - Number of objects/entries to pop
 633  *              walk_state          - Current Walk state
 634  *
 635  * RETURN:      Status
 636  *
 637  * DESCRIPTION: Pop this walk's object stack and delete each object that is
 638  *              popped off.
 639  *
 640  ******************************************************************************/
 641
 642 acpi_status
 643 acpi_ds_obj_stack_pop_and_delete (
 644         u32                             pop_count,
 645         struct acpi_walk_state          *walk_state)
 646 {
 647         u32                             i;
 648         union acpi_operand_object       *obj_desc;
 649
 650
 651         ACPI_FUNCTION_NAME ("ds_obj_stack_pop_and_delete");
 652
 653
 654         for (i = 0; i < pop_count; i++) {
 655                 /* Check for stack underflow */
 656
 657                 if (walk_state->num_operands == 0) {
 658                         ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
 659                                 "Underflow! Count=%X State=%p #Ops=%X\n",
 660                                 pop_count, walk_state, walk_state->num_operands));
 661                         return (AE_STACK_UNDERFLOW);
 662                 }
 663
 664                 /* Pop the stack and delete an object if present in this stack entry */
 665
 666                 walk_state->num_operands--;
 667                 obj_desc = walk_state->operands [walk_state->num_operands];
 668                 if (obj_desc) {
 669                         acpi_ut_remove_reference (walk_state->operands [walk_state->num_operands]);
 670                         walk_state->operands [walk_state->num_operands] = NULL;
 671                 }
 672         }
 673
 674         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Count=%X State=%p #Ops=%X\n",
 675                           pop_count, walk_state, walk_state->num_operands));
 676
 677         return (AE_OK);
 678 }
 679
 680
 681 /*******************************************************************************
 682  *
 683  * FUNCTION:    acpi_ds_obj_stack_get_value
 684  *
 685  * PARAMETERS:  Index               - Stack index whose value is desired.  Based
 686  *                                    on the top of the stack (index=0 == top)
 687  *              walk_state          - Current Walk state
 688  *
 689  * RETURN:      Status
 690  *
 691  * DESCRIPTION: Retrieve an object from this walk's object stack.  Index must
 692  *              be within the range of the current stack pointer.
 693  *
 694  ******************************************************************************/
 695 #ifdef ACPI_FUTURE_USAGE
 696 void *
 697 acpi_ds_obj_stack_get_value (
 698         u32                             index,
 699         struct acpi_walk_state          *walk_state)
 700 {
 701
 702         ACPI_FUNCTION_TRACE_PTR ("ds_obj_stack_get_value", walk_state);
 703
 704
 705         /* Can't do it if the stack is empty */
 706
 707         if (walk_state->num_operands == 0) {
 708                 return_PTR (NULL);
 709         }
 710
 711         /* or if the index is past the top of the stack */
 712
 713         if (index > (walk_state->num_operands - (u32) 1)) {
 714                 return_PTR (NULL);
 715         }
 716
 717         return_PTR (walk_state->operands[(acpi_native_uint)(walk_state->num_operands - 1) -
 718                           index]);
 719 }
 720 #endif  /*  ACPI_FUTURE_USAGE  */
 721
 722
 723 /*******************************************************************************
 724  *
 725  * FUNCTION:    acpi_ds_get_current_walk_state
 726  *
 727  * PARAMETERS:  Thread          - Get current active state for this Thread
 728  *
 729  * RETURN:      Pointer to the current walk state
 730  *
 731  * DESCRIPTION: Get the walk state that is at the head of the list (the "current"
 732  *              walk state.)
 733  *
 734  ******************************************************************************/
 735
 736 struct acpi_walk_state *
 737 acpi_ds_get_current_walk_state (
 738         struct acpi_thread_state        *thread)
 739
 740 {
 741         ACPI_FUNCTION_NAME ("ds_get_current_walk_state");
 742
 743
 744         if (!thread) {
 745                 return (NULL);
 746         }
 747
 748         ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, "Current walk_state %p\n",
 749                 thread->walk_state_list));
 750
 751         return (thread->walk_state_list);
 752 }
 753
 754
 755 /*******************************************************************************
 756  *
 757  * FUNCTION:    acpi_ds_push_walk_state
 758  *
 759  * PARAMETERS:  walk_state      - State to push
 760  *              walk_list       - The list that owns the walk stack
 761  *
 762  * RETURN:      None
 763  *
 764  * DESCRIPTION: Place the walk_state at the head of the state list.
 765  *
 766  ******************************************************************************/
 767
 768 void
 769 acpi_ds_push_walk_state (
 770         struct acpi_walk_state          *walk_state,
 771         struct acpi_thread_state        *thread)
 772 {
 773         ACPI_FUNCTION_TRACE ("ds_push_walk_state");
 774
 775
 776         walk_state->next      = thread->walk_state_list;
 777         thread->walk_state_list = walk_state;
 778
 779         return_VOID;
 780 }
 781
 782
 783 /*******************************************************************************
 784  *
 785  * FUNCTION:    acpi_ds_pop_walk_state
 786  *
 787  * PARAMETERS:  walk_list       - The list that owns the walk stack
 788  *
 789  * RETURN:      A walk_state object popped from the stack
 790  *
 791  * DESCRIPTION: Remove and return the walkstate object that is at the head of
 792  *              the walk stack for the given walk list.  NULL indicates that
 793  *              the list is empty.
 794  *
 795  ******************************************************************************/
 796
 797 struct acpi_walk_state *
 798 acpi_ds_pop_walk_state (
 799         struct acpi_thread_state        *thread)
 800 {
 801         struct acpi_walk_state          *walk_state;
 802
 803
 804         ACPI_FUNCTION_TRACE ("ds_pop_walk_state");
 805
 806
 807         walk_state = thread->walk_state_list;
 808
 809         if (walk_state) {
 810                 /* Next walk state becomes the current walk state */
 811
 812                 thread->walk_state_list = walk_state->next;
 813
 814                 /*
 815                  * Don't clear the NEXT field, this serves as an indicator
 816                  * that there is a parent WALK STATE
 817                  *     NO: walk_state->Next = NULL;
 818                  */
 819         }
 820
 821         return_PTR (walk_state);
 822 }
 823
 824
 825 /*******************************************************************************
 826  *
 827  * FUNCTION:    acpi_ds_create_walk_state
 828  *
 829  * PARAMETERS:  Origin          - Starting point for this walk
 830  *              Thread          - Current thread state
 831  *
 832  * RETURN:      Pointer to the new walk state.
 833  *
 834  * DESCRIPTION: Allocate and initialize a new walk state.  The current walk
 835  *              state is set to this new state.
 836  *
 837  ******************************************************************************/
 838
 839 struct acpi_walk_state *
 840 acpi_ds_create_walk_state (
 841         acpi_owner_id                   owner_id,
 842         union acpi_parse_object         *origin,
 843         union acpi_operand_object       *mth_desc,
 844         struct acpi_thread_state        *thread)
 845 {
 846         struct acpi_walk_state          *walk_state;
 847         acpi_status                     status;
 848
 849
 850         ACPI_FUNCTION_TRACE ("ds_create_walk_state");
 851
 852
 853         walk_state = acpi_ut_acquire_from_cache (ACPI_MEM_LIST_WALK);
 854         if (!walk_state) {
 855                 return_PTR (NULL);
 856         }
 857
 858         walk_state->data_type       = ACPI_DESC_TYPE_WALK;
 859         walk_state->owner_id        = owner_id;
 860         walk_state->origin          = origin;
 861         walk_state->method_desc     = mth_desc;
 862         walk_state->thread          = thread;
 863
 864         walk_state->parser_state.start_op = origin;
 865
 866         /* Init the method args/local */
 867
 868 #if (!defined (ACPI_NO_METHOD_EXECUTION) && !defined (ACPI_CONSTANT_EVAL_ONLY))
 869         acpi_ds_method_data_init (walk_state);
 870 #endif
 871
 872         /* Create an initial result stack entry */
 873
 874         status = acpi_ds_result_stack_push (walk_state);
 875         if (ACPI_FAILURE (status)) {
 876                 acpi_ut_release_to_cache (ACPI_MEM_LIST_WALK, walk_state);
 877                 return_PTR (NULL);
 878         }
 879
 880         /* Put the new state at the head of the walk list */
 881
 882         if (thread) {
 883                 acpi_ds_push_walk_state (walk_state, thread);
 884         }
 885
 886         return_PTR (walk_state);
 887 }
 888
 889
 890 /*******************************************************************************
 891  *
 892  * FUNCTION:    acpi_ds_init_aml_walk
 893  *
 894  * PARAMETERS:  walk_state      - New state to be initialized
 895  *              Op              - Current parse op
 896  *              method_node     - Control method NS node, if any
 897  *              aml_start       - Start of AML
 898  *              aml_length      - Length of AML
 899  *              Params          - Method args, if any
 900  *              return_obj_desc - Where to store a return object, if any
 901  *              pass_number     - 1, 2, or 3
 902  *
 903  * RETURN:      Status
 904  *
 905  * DESCRIPTION: Initialize a walk state for a pass 1 or 2 parse tree walk
 906  *
 907  ******************************************************************************/
 908
 909 acpi_status
 910 acpi_ds_init_aml_walk (
 911         struct acpi_walk_state          *walk_state,
 912         union acpi_parse_object         *op,
 913         struct acpi_namespace_node      *method_node,
 914         u8                              *aml_start,
 915         u32                             aml_length,
 916         struct acpi_parameter_info      *info,
 917         u32                             pass_number)
 918 {
 919         acpi_status                     status;
 920         struct acpi_parse_state         *parser_state = &walk_state->parser_state;
 921         union acpi_parse_object         *extra_op;
 922
 923
 924         ACPI_FUNCTION_TRACE ("ds_init_aml_walk");
 925
 926
 927         walk_state->parser_state.aml    =
 928         walk_state->parser_state.aml_start = aml_start;
 929         walk_state->parser_state.aml_end =
 930         walk_state->parser_state.pkg_end = aml_start + aml_length;
 931
 932         /* The next_op of the next_walk will be the beginning of the method */
 933
 934         walk_state->next_op             = NULL;
 935
 936         if (info) {
 937                 if (info->parameter_type == ACPI_PARAM_GPE) {
 938                         walk_state->gpe_event_info = ACPI_CAST_PTR (struct acpi_gpe_event_info,
 939                                            info->parameters);
 940                 }
 941                 else {
 942                         walk_state->params              = info->parameters;
 943                         walk_state->caller_return_desc  = &info->return_object;
 944                 }
 945         }
 946
 947         status = acpi_ps_init_scope (&walk_state->parser_state, op);
 948         if (ACPI_FAILURE (status)) {
 949                 return_ACPI_STATUS (status);
 950         }
 951
 952         if (method_node) {
 953                 walk_state->parser_state.start_node = method_node;
 954                 walk_state->walk_type            = ACPI_WALK_METHOD;
 955                 walk_state->method_node          = method_node;
 956                 walk_state->method_desc          = acpi_ns_get_attached_object (method_node);
 957
 958                 /* Push start scope on scope stack and make it current  */
 959
 960                 status = acpi_ds_scope_stack_push (method_node, ACPI_TYPE_METHOD, walk_state);
 961                 if (ACPI_FAILURE (status)) {
 962                         return_ACPI_STATUS (status);
 963                 }
 964
 965                 /* Init the method arguments */
 966
 967                 status = acpi_ds_method_data_init_args (walk_state->params, ACPI_METHOD_NUM_ARGS, walk_state);
 968                 if (ACPI_FAILURE (status)) {
 969                         return_ACPI_STATUS (status);
 970                 }
 971         }
 972         else {
 973                 /*
 974                  * Setup the current scope.
 975                  * Find a Named Op that has a namespace node associated with it.
 976                  * search upwards from this Op.  Current scope is the first
 977                  * Op with a namespace node.
 978                  */
 979                 extra_op = parser_state->start_op;
 980                 while (extra_op && !extra_op->common.node) {
 981                         extra_op = extra_op->common.parent;
 982                 }
 983
 984                 if (!extra_op) {
 985                         parser_state->start_node = NULL;
 986                 }
 987                 else {
 988                         parser_state->start_node = extra_op->common.node;
 989                 }
 990
 991                 if (parser_state->start_node) {
 992                         /* Push start scope on scope stack and make it current  */
 993
 994                         status = acpi_ds_scope_stack_push (parser_state->start_node,
 995                                           parser_state->start_node->type, walk_state);
 996                         if (ACPI_FAILURE (status)) {
 997                                 return_ACPI_STATUS (status);
 998                         }
 999                 }
1000         }
1001
1002         status = acpi_ds_init_callbacks (walk_state, pass_number);
1003         return_ACPI_STATUS (status);
1004 }
1005
1006
1007 /*******************************************************************************
1008  *
1009  * FUNCTION:    acpi_ds_delete_walk_state
1010  *
1011  * PARAMETERS:  walk_state      - State to delete
1012  *
1013  * RETURN:      Status
1014  *
1015  * DESCRIPTION: Delete a walk state including all internal data structures
1016  *
1017  ******************************************************************************/
1018
1019 void
1020 acpi_ds_delete_walk_state (
1021         struct acpi_walk_state          *walk_state)
1022 {
1023         union acpi_generic_state        *state;
1024
1025
1026         ACPI_FUNCTION_TRACE_PTR ("ds_delete_walk_state", walk_state);
1027
1028
1029         if (!walk_state) {
1030                 return;
1031         }
1032
1033         if (walk_state->data_type != ACPI_DESC_TYPE_WALK) {
1034                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "%p is not a valid walk state\n", walk_state));
1035                 return;
1036         }
1037
1038         if (walk_state->parser_state.scope) {
1039                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "%p walk still has a scope list\n", walk_state));
1040         }
1041
1042         /* Always must free any linked control states */
1043
1044         while (walk_state->control_state) {
1045                 state = walk_state->control_state;
1046                 walk_state->control_state = state->common.next;
1047
1048                 acpi_ut_delete_generic_state (state);
1049         }
1050
1051         /* Always must free any linked parse states */
1052
1053         while (walk_state->scope_info) {
1054                 state = walk_state->scope_info;
1055                 walk_state->scope_info = state->common.next;
1056
1057                 acpi_ut_delete_generic_state (state);
1058         }
1059
1060         /* Always must free any stacked result states */
1061
1062         while (walk_state->results) {
1063                 state = walk_state->results;
1064                 walk_state->results = state->common.next;
1065
1066                 acpi_ut_delete_generic_state (state);
1067         }
1068
1069         acpi_ut_release_to_cache (ACPI_MEM_LIST_WALK, walk_state);
1070         return_VOID;
1071 }
1072
1073
1074 #ifdef ACPI_ENABLE_OBJECT_CACHE
1075 /******************************************************************************
1076  *
1077  * FUNCTION:    acpi_ds_delete_walk_state_cache
1078  *
1079  * PARAMETERS:  None
1080  *
1081  * RETURN:      Status
1082  *
1083  * DESCRIPTION: Purge the global state object cache.  Used during subsystem
1084  *              termination.
1085  *
1086  ******************************************************************************/
1087
1088 void
1089 acpi_ds_delete_walk_state_cache (
1090         void)
1091 {
1092         ACPI_FUNCTION_TRACE ("ds_delete_walk_state_cache");
1093
1094
1095         acpi_ut_delete_generic_cache (ACPI_MEM_LIST_WALK);
1096         return_VOID;
1097 }
1098 #endif
1099
1100