drivers/acpi/parser/psloop.c

   1 /******************************************************************************
   2  *
   3  * Module Name: psloop - Main AML parse loop
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2006, 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  * Parse the AML and build an operation tree as most interpreters,
  46  * like Perl, do.  Parsing is done by hand rather than with a YACC
  47  * generated parser to tightly constrain stack and dynamic memory
  48  * usage.  At the same time, parsing is kept flexible and the code
  49  * fairly compact by parsing based on a list of AML opcode
  50  * templates in aml_op_info[]
  51  */
  52
  53 #include <acpi/acpi.h>
  54 #include <acpi/acparser.h>
  55 #include <acpi/acdispat.h>
  56 #include <acpi/amlcode.h>
  57
  58 #define _COMPONENT          ACPI_PARSER
  59 ACPI_MODULE_NAME("psloop")
  60
  61 static u32 acpi_gbl_depth = 0;
  62
  63 /*******************************************************************************
  64  *
  65  * FUNCTION:    acpi_ps_parse_loop
  66  *
  67  * PARAMETERS:  walk_state          - Current state
  68  *
  69  * RETURN:      Status
  70  *
  71  * DESCRIPTION: Parse AML (pointed to by the current parser state) and return
  72  *              a tree of ops.
  73  *
  74  ******************************************************************************/
  75
  76 acpi_status acpi_ps_parse_loop(struct acpi_walk_state *walk_state)
  77 {
  78         acpi_status status = AE_OK;
  79         acpi_status status2;
  80         union acpi_parse_object *op = NULL;     /* current op */
  81         union acpi_parse_object *arg = NULL;
  82         union acpi_parse_object *pre_op = NULL;
  83         struct acpi_parse_state *parser_state;
  84         u8 *aml_op_start = NULL;
  85
  86         ACPI_FUNCTION_TRACE_PTR("ps_parse_loop", walk_state);
  87
  88         if (walk_state->descending_callback == NULL) {
  89                 return_ACPI_STATUS(AE_BAD_PARAMETER);
  90         }
  91
  92         parser_state = &walk_state->parser_state;
  93         walk_state->arg_types = 0;
  94
  95 #if (!defined (ACPI_NO_METHOD_EXECUTION) && !defined (ACPI_CONSTANT_EVAL_ONLY))
  96
  97         if (walk_state->walk_type & ACPI_WALK_METHOD_RESTART) {
  98                 /* We are restarting a preempted control method */
  99
 100                 if (acpi_ps_has_completed_scope(parser_state)) {
 101                         /*
 102                          * We must check if a predicate to an IF or WHILE statement
 103                          * was just completed
 104                          */
 105                         if ((parser_state->scope->parse_scope.op) &&
 106                             ((parser_state->scope->parse_scope.op->common.
 107                               aml_opcode == AML_IF_OP)
 108                              || (parser_state->scope->parse_scope.op->common.
 109                                  aml_opcode == AML_WHILE_OP))
 110                             && (walk_state->control_state)
 111                             && (walk_state->control_state->common.state ==
 112                                 ACPI_CONTROL_PREDICATE_EXECUTING)) {
 113                                 /*
 114                                  * A predicate was just completed, get the value of the
 115                                  * predicate and branch based on that value
 116                                  */
 117                                 walk_state->op = NULL;
 118                                 status =
 119                                     acpi_ds_get_predicate_value(walk_state,
 120                                                                 ACPI_TO_POINTER
 121                                                                 (TRUE));
 122                                 if (ACPI_FAILURE(status)
 123                                     && ((status & AE_CODE_MASK) !=
 124                                         AE_CODE_CONTROL)) {
 125                                         if (status == AE_AML_NO_RETURN_VALUE) {
 126                                                 ACPI_EXCEPTION((AE_INFO, status,
 127                                                                 "Invoked method did not return a value"));
 128
 129                                         }
 130                                         ACPI_EXCEPTION((AE_INFO, status,
 131                                                         "get_predicate Failed"));
 132                                         return_ACPI_STATUS(status);
 133                                 }
 134
 135                                 status =
 136                                     acpi_ps_next_parse_state(walk_state, op,
 137                                                              status);
 138                         }
 139
 140                         acpi_ps_pop_scope(parser_state, &op,
 141                                           &walk_state->arg_types,
 142                                           &walk_state->arg_count);
 143                         ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
 144                                           "Popped scope, Op=%p\n", op));
 145                 } else if (walk_state->prev_op) {
 146                         /* We were in the middle of an op */
 147
 148                         op = walk_state->prev_op;
 149                         walk_state->arg_types = walk_state->prev_arg_types;
 150                 }
 151         }
 152 #endif
 153
 154         /* Iterative parsing loop, while there is more AML to process: */
 155
 156         while ((parser_state->aml < parser_state->aml_end) || (op)) {
 157                 aml_op_start = parser_state->aml;
 158                 if (!op) {
 159                         /* Get the next opcode from the AML stream */
 160
 161                         walk_state->aml_offset =
 162                             (u32) ACPI_PTR_DIFF(parser_state->aml,
 163                                                 parser_state->aml_start);
 164                         walk_state->opcode = acpi_ps_peek_opcode(parser_state);
 165
 166                         /*
 167                          * First cut to determine what we have found:
 168                          * 1) A valid AML opcode
 169                          * 2) A name string
 170                          * 3) An unknown/invalid opcode
 171                          */
 172                         walk_state->op_info =
 173                             acpi_ps_get_opcode_info(walk_state->opcode);
 174                         switch (walk_state->op_info->class) {
 175                         case AML_CLASS_ASCII:
 176                         case AML_CLASS_PREFIX:
 177                                 /*
 178                                  * Starts with a valid prefix or ASCII char, this is a name
 179                                  * string.  Convert the bare name string to a namepath.
 180                                  */
 181                                 walk_state->opcode = AML_INT_NAMEPATH_OP;
 182                                 walk_state->arg_types = ARGP_NAMESTRING;
 183                                 break;
 184
 185                         case AML_CLASS_UNKNOWN:
 186
 187                                 /* The opcode is unrecognized.  Just skip unknown opcodes */
 188
 189                                 ACPI_ERROR((AE_INFO,
 190                                             "Found unknown opcode %X at AML address %p offset %X, ignoring",
 191                                             walk_state->opcode,
 192                                             parser_state->aml,
 193                                             walk_state->aml_offset));
 194
 195                                 ACPI_DUMP_BUFFER(parser_state->aml, 128);
 196
 197                                 /* Assume one-byte bad opcode */
 198
 199                                 parser_state->aml++;
 200                                 continue;
 201
 202                         default:
 203
 204                                 /* Found opcode info, this is a normal opcode */
 205
 206                                 parser_state->aml +=
 207                                     acpi_ps_get_opcode_size(walk_state->opcode);
 208                                 walk_state->arg_types =
 209                                     walk_state->op_info->parse_args;
 210                                 break;
 211                         }
 212
 213                         /* Create Op structure and append to parent's argument list */
 214
 215                         if (walk_state->op_info->flags & AML_NAMED) {
 216                                 /* Allocate a new pre_op if necessary */
 217
 218                                 if (!pre_op) {
 219                                         pre_op =
 220                                             acpi_ps_alloc_op(walk_state->
 221                                                              opcode);
 222                                         if (!pre_op) {
 223                                                 status = AE_NO_MEMORY;
 224                                                 goto close_this_op;
 225                                         }
 226                                 }
 227
 228                                 pre_op->common.value.arg = NULL;
 229                                 pre_op->common.aml_opcode = walk_state->opcode;
 230
 231                                 /*
 232                                  * Get and append arguments until we find the node that contains
 233                                  * the name (the type ARGP_NAME).
 234                                  */
 235                                 while (GET_CURRENT_ARG_TYPE
 236                                        (walk_state->arg_types)
 237                                        &&
 238                                        (GET_CURRENT_ARG_TYPE
 239                                         (walk_state->arg_types) != ARGP_NAME)) {
 240                                         status =
 241                                             acpi_ps_get_next_arg(walk_state,
 242                                                                  parser_state,
 243                                                                  GET_CURRENT_ARG_TYPE
 244                                                                  (walk_state->
 245                                                                   arg_types),
 246                                                                  &arg);
 247                                         if (ACPI_FAILURE(status)) {
 248                                                 goto close_this_op;
 249                                         }
 250
 251                                         acpi_ps_append_arg(pre_op, arg);
 252                                         INCREMENT_ARG_LIST(walk_state->
 253                                                            arg_types);
 254                                 }
 255
 256                                 /*
 257                                  * Make sure that we found a NAME and didn't run out of
 258                                  * arguments
 259                                  */
 260                                 if (!GET_CURRENT_ARG_TYPE
 261                                     (walk_state->arg_types)) {
 262                                         status = AE_AML_NO_OPERAND;
 263                                         goto close_this_op;
 264                                 }
 265
 266                                 /* We know that this arg is a name, move to next arg */
 267
 268                                 INCREMENT_ARG_LIST(walk_state->arg_types);
 269
 270                                 /*
 271                                  * Find the object.  This will either insert the object into
 272                                  * the namespace or simply look it up
 273                                  */
 274                                 walk_state->op = NULL;
 275
 276                                 status =
 277                                     walk_state->descending_callback(walk_state,
 278                                                                     &op);
 279                                 if (ACPI_FAILURE(status)) {
 280                                         ACPI_EXCEPTION((AE_INFO, status,
 281                                                         "During name lookup/catalog"));
 282                                         goto close_this_op;
 283                                 }
 284
 285                                 if (!op) {
 286                                         continue;
 287                                 }
 288
 289                                 status =
 290                                     acpi_ps_next_parse_state(walk_state, op,
 291                                                              status);
 292                                 if (status == AE_CTRL_PENDING) {
 293                                         status = AE_OK;
 294                                         goto close_this_op;
 295                                 }
 296
 297                                 if (ACPI_FAILURE(status)) {
 298                                         goto close_this_op;
 299                                 }
 300
 301                                 acpi_ps_append_arg(op,
 302                                                    pre_op->common.value.arg);
 303                                 acpi_gbl_depth++;
 304
 305                                 if (op->common.aml_opcode == AML_REGION_OP) {
 306                                         /*
 307                                          * Defer final parsing of an operation_region body,
 308                                          * because we don't have enough info in the first pass
 309                                          * to parse it correctly (i.e., there may be method
 310                                          * calls within the term_arg elements of the body.)
 311                                          *
 312                                          * However, we must continue parsing because
 313                                          * the opregion is not a standalone package --
 314                                          * we don't know where the end is at this point.
 315                                          *
 316                                          * (Length is unknown until parse of the body complete)
 317                                          */
 318                                         op->named.data = aml_op_start;
 319                                         op->named.length = 0;
 320                                 }
 321                         } else {
 322                                 /* Not a named opcode, just allocate Op and append to parent */
 323
 324                                 walk_state->op_info =
 325                                     acpi_ps_get_opcode_info(walk_state->opcode);
 326                                 op = acpi_ps_alloc_op(walk_state->opcode);
 327                                 if (!op) {
 328                                         status = AE_NO_MEMORY;
 329                                         goto close_this_op;
 330                                 }
 331
 332                                 if (walk_state->op_info->flags & AML_CREATE) {
 333                                         /*
 334                                          * Backup to beginning of create_xXXfield declaration
 335                                          * body_length is unknown until we parse the body
 336                                          */
 337                                         op->named.data = aml_op_start;
 338                                         op->named.length = 0;
 339                                 }
 340
 341                                 acpi_ps_append_arg(acpi_ps_get_parent_scope
 342                                                    (parser_state), op);
 343
 344                                 if ((walk_state->descending_callback != NULL)) {
 345                                         /*
 346                                          * Find the object. This will either insert the object into
 347                                          * the namespace or simply look it up
 348                                          */
 349                                         walk_state->op = op;
 350
 351                                         status =
 352                                             walk_state->
 353                                             descending_callback(walk_state,
 354                                                                 &op);
 355                                         status =
 356                                             acpi_ps_next_parse_state(walk_state,
 357                                                                      op,
 358                                                                      status);
 359                                         if (status == AE_CTRL_PENDING) {
 360                                                 status = AE_OK;
 361                                                 goto close_this_op;
 362                                         }
 363
 364                                         if (ACPI_FAILURE(status)) {
 365                                                 goto close_this_op;
 366                                         }
 367                                 }
 368                         }
 369
 370                         op->common.aml_offset = walk_state->aml_offset;
 371
 372                         if (walk_state->op_info) {
 373                                 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
 374                                                   "Opcode %4.4X [%s] Op %p Aml %p aml_offset %5.5X\n",
 375                                                   (u32) op->common.aml_opcode,
 376                                                   walk_state->op_info->name, op,
 377                                                   parser_state->aml,
 378                                                   op->common.aml_offset));
 379                         }
 380                 }
 381
 382                 /*
 383                  * Start arg_count at zero because we don't know if there are
 384                  * any args yet
 385                  */
 386                 walk_state->arg_count = 0;
 387
 388                 /* Are there any arguments that must be processed? */
 389
 390                 if (walk_state->arg_types) {
 391                         /* Get arguments */
 392
 393                         switch (op->common.aml_opcode) {
 394                         case AML_BYTE_OP:       /* AML_BYTEDATA_ARG */
 395                         case AML_WORD_OP:       /* AML_WORDDATA_ARG */
 396                         case AML_DWORD_OP:      /* AML_DWORDATA_ARG */
 397                         case AML_QWORD_OP:      /* AML_QWORDATA_ARG */
 398                         case AML_STRING_OP:     /* AML_ASCIICHARLIST_ARG */
 399
 400                                 /* Fill in constant or string argument directly */
 401
 402                                 acpi_ps_get_next_simple_arg(parser_state,
 403                                                             GET_CURRENT_ARG_TYPE
 404                                                             (walk_state->
 405                                                              arg_types), op);
 406                                 break;
 407
 408                         case AML_INT_NAMEPATH_OP:       /* AML_NAMESTRING_ARG */
 409
 410                                 status =
 411                                     acpi_ps_get_next_namepath(walk_state,
 412                                                               parser_state, op,
 413                                                               1);
 414                                 if (ACPI_FAILURE(status)) {
 415                                         goto close_this_op;
 416                                 }
 417
 418                                 walk_state->arg_types = 0;
 419                                 break;
 420
 421                         default:
 422                                 /*
 423                                  * Op is not a constant or string, append each argument
 424                                  * to the Op
 425                                  */
 426                                 while (GET_CURRENT_ARG_TYPE
 427                                        (walk_state->arg_types)
 428                                        && !walk_state->arg_count) {
 429                                         walk_state->aml_offset = (u32)
 430                                             ACPI_PTR_DIFF(parser_state->aml,
 431                                                           parser_state->
 432                                                           aml_start);
 433
 434                                         status =
 435                                             acpi_ps_get_next_arg(walk_state,
 436                                                                  parser_state,
 437                                                                  GET_CURRENT_ARG_TYPE
 438                                                                  (walk_state->
 439                                                                   arg_types),
 440                                                                  &arg);
 441                                         if (ACPI_FAILURE(status)) {
 442                                                 goto close_this_op;
 443                                         }
 444
 445                                         if (arg) {
 446                                                 arg->common.aml_offset =
 447                                                     walk_state->aml_offset;
 448                                                 acpi_ps_append_arg(op, arg);
 449                                         }
 450                                         INCREMENT_ARG_LIST(walk_state->
 451                                                            arg_types);
 452                                 }
 453
 454                                 /* Special processing for certain opcodes */
 455
 456                                 /* TBD (remove): Temporary mechanism to disable this code if needed */
 457
 458 #ifdef ACPI_ENABLE_MODULE_LEVEL_CODE
 459
 460                                 if ((walk_state->pass_number <=
 461                                      ACPI_IMODE_LOAD_PASS1)
 462                                     &&
 463                                     ((walk_state->
 464                                       parse_flags & ACPI_PARSE_DISASSEMBLE) ==
 465                                      0)) {
 466                                         /*
 467                                          * We want to skip If/Else/While constructs during Pass1
 468                                          * because we want to actually conditionally execute the
 469                                          * code during Pass2.
 470                                          *
 471                                          * Except for disassembly, where we always want to
 472                                          * walk the If/Else/While packages
 473                                          */
 474                                         switch (op->common.aml_opcode) {
 475                                         case AML_IF_OP:
 476                                         case AML_ELSE_OP:
 477                                         case AML_WHILE_OP:
 478
 479                                                 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
 480                                                                   "Pass1: Skipping an If/Else/While body\n"));
 481
 482                                                 /* Skip body of if/else/while in pass 1 */
 483
 484                                                 parser_state->aml =
 485                                                     parser_state->pkg_end;
 486                                                 walk_state->arg_count = 0;
 487                                                 break;
 488
 489                                         default:
 490                                                 break;
 491                                         }
 492                                 }
 493 #endif
 494                                 switch (op->common.aml_opcode) {
 495                                 case AML_METHOD_OP:
 496
 497                                         /*
 498                                          * Skip parsing of control method
 499                                          * because we don't have enough info in the first pass
 500                                          * to parse it correctly.
 501                                          *
 502                                          * Save the length and address of the body
 503                                          */
 504                                         op->named.data = parser_state->aml;
 505                                         op->named.length =
 506                                             (u32) (parser_state->pkg_end -
 507                                                    parser_state->aml);
 508
 509                                         /* Skip body of method */
 510
 511                                         parser_state->aml =
 512                                             parser_state->pkg_end;
 513                                         walk_state->arg_count = 0;
 514                                         break;
 515
 516                                 case AML_BUFFER_OP:
 517                                 case AML_PACKAGE_OP:
 518                                 case AML_VAR_PACKAGE_OP:
 519
 520                                         if ((op->common.parent) &&
 521                                             (op->common.parent->common.
 522                                              aml_opcode == AML_NAME_OP)
 523                                             && (walk_state->pass_number <=
 524                                                 ACPI_IMODE_LOAD_PASS2)) {
 525                                                 /*
 526                                                  * Skip parsing of Buffers and Packages
 527                                                  * because we don't have enough info in the first pass
 528                                                  * to parse them correctly.
 529                                                  */
 530                                                 op->named.data = aml_op_start;
 531                                                 op->named.length =
 532                                                     (u32) (parser_state->
 533                                                            pkg_end -
 534                                                            aml_op_start);
 535
 536                                                 /* Skip body */
 537
 538                                                 parser_state->aml =
 539                                                     parser_state->pkg_end;
 540                                                 walk_state->arg_count = 0;
 541                                         }
 542                                         break;
 543
 544                                 case AML_WHILE_OP:
 545
 546                                         if (walk_state->control_state) {
 547                                                 walk_state->control_state->
 548                                                     control.package_end =
 549                                                     parser_state->pkg_end;
 550                                         }
 551                                         break;
 552
 553                                 default:
 554
 555                                         /* No action for all other opcodes */
 556                                         break;
 557                                 }
 558                                 break;
 559                         }
 560                 }
 561
 562                 /* Check for arguments that need to be processed */
 563
 564                 if (walk_state->arg_count) {
 565                         /*
 566                          * There are arguments (complex ones), push Op and
 567                          * prepare for argument
 568                          */
 569                         status = acpi_ps_push_scope(parser_state, op,
 570                                                     walk_state->arg_types,
 571                                                     walk_state->arg_count);
 572                         if (ACPI_FAILURE(status)) {
 573                                 goto close_this_op;
 574                         }
 575                         op = NULL;
 576                         continue;
 577                 }
 578
 579                 /*
 580                  * All arguments have been processed -- Op is complete,
 581                  * prepare for next
 582                  */
 583                 walk_state->op_info =
 584                     acpi_ps_get_opcode_info(op->common.aml_opcode);
 585                 if (walk_state->op_info->flags & AML_NAMED) {
 586                         if (acpi_gbl_depth) {
 587                                 acpi_gbl_depth--;
 588                         }
 589
 590                         if (op->common.aml_opcode == AML_REGION_OP) {
 591                                 /*
 592                                  * Skip parsing of control method or opregion body,
 593                                  * because we don't have enough info in the first pass
 594                                  * to parse them correctly.
 595                                  *
 596                                  * Completed parsing an op_region declaration, we now
 597                                  * know the length.
 598                                  */
 599                                 op->named.length =
 600                                     (u32) (parser_state->aml - op->named.data);
 601                         }
 602                 }
 603
 604                 if (walk_state->op_info->flags & AML_CREATE) {
 605                         /*
 606                          * Backup to beginning of create_xXXfield declaration (1 for
 607                          * Opcode)
 608                          *
 609                          * body_length is unknown until we parse the body
 610                          */
 611                         op->named.length =
 612                             (u32) (parser_state->aml - op->named.data);
 613                 }
 614
 615                 /* This op complete, notify the dispatcher */
 616
 617                 if (walk_state->ascending_callback != NULL) {
 618                         walk_state->op = op;
 619                         walk_state->opcode = op->common.aml_opcode;
 620
 621                         status = walk_state->ascending_callback(walk_state);
 622                         status =
 623                             acpi_ps_next_parse_state(walk_state, op, status);
 624                         if (status == AE_CTRL_PENDING) {
 625                                 status = AE_OK;
 626                                 goto close_this_op;
 627                         }
 628                 }
 629
 630               close_this_op:
 631                 /*
 632                  * Finished one argument of the containing scope
 633                  */
 634                 parser_state->scope->parse_scope.arg_count--;
 635
 636                 /* Finished with pre_op */
 637
 638                 if (pre_op) {
 639                         acpi_ps_free_op(pre_op);
 640                         pre_op = NULL;
 641                 }
 642
 643                 /* Close this Op (will result in parse subtree deletion) */
 644
 645                 status2 = acpi_ps_complete_this_op(walk_state, op);
 646                 if (ACPI_FAILURE(status2)) {
 647                         return_ACPI_STATUS(status2);
 648                 }
 649                 op = NULL;
 650
 651                 switch (status) {
 652                 case AE_OK:
 653                         break;
 654
 655                 case AE_CTRL_TRANSFER:
 656
 657                         /* We are about to transfer to a called method. */
 658
 659                         walk_state->prev_op = op;
 660                         walk_state->prev_arg_types = walk_state->arg_types;
 661                         return_ACPI_STATUS(status);
 662
 663                 case AE_CTRL_END:
 664
 665                         acpi_ps_pop_scope(parser_state, &op,
 666                                           &walk_state->arg_types,
 667                                           &walk_state->arg_count);
 668
 669                         if (op) {
 670                                 walk_state->op = op;
 671                                 walk_state->op_info =
 672                                     acpi_ps_get_opcode_info(op->common.
 673                                                             aml_opcode);
 674                                 walk_state->opcode = op->common.aml_opcode;
 675
 676                                 status =
 677                                     walk_state->ascending_callback(walk_state);
 678                                 status =
 679                                     acpi_ps_next_parse_state(walk_state, op,
 680                                                              status);
 681
 682                                 status2 =
 683                                     acpi_ps_complete_this_op(walk_state, op);
 684                                 if (ACPI_FAILURE(status2)) {
 685                                         return_ACPI_STATUS(status2);
 686                                 }
 687                                 op = NULL;
 688                         }
 689                         status = AE_OK;
 690                         break;
 691
 692                 case AE_CTRL_BREAK:
 693                 case AE_CTRL_CONTINUE:
 694
 695                         /* Pop off scopes until we find the While */
 696
 697                         while (!op || (op->common.aml_opcode != AML_WHILE_OP)) {
 698                                 acpi_ps_pop_scope(parser_state, &op,
 699                                                   &walk_state->arg_types,
 700                                                   &walk_state->arg_count);
 701
 702                                 if (op->common.aml_opcode != AML_WHILE_OP) {
 703                                         status2 =
 704                                             acpi_ds_result_stack_pop
 705                                             (walk_state);
 706                                         if (ACPI_FAILURE(status2)) {
 707                                                 return_ACPI_STATUS(status2);
 708                                         }
 709                                 }
 710                         }
 711
 712                         /* Close this iteration of the While loop */
 713
 714                         walk_state->op = op;
 715                         walk_state->op_info =
 716                             acpi_ps_get_opcode_info(op->common.aml_opcode);
 717                         walk_state->opcode = op->common.aml_opcode;
 718
 719                         status = walk_state->ascending_callback(walk_state);
 720                         status =
 721                             acpi_ps_next_parse_state(walk_state, op, status);
 722
 723                         status2 = acpi_ps_complete_this_op(walk_state, op);
 724                         if (ACPI_FAILURE(status2)) {
 725                                 return_ACPI_STATUS(status2);
 726                         }
 727                         op = NULL;
 728
 729                         status = AE_OK;
 730                         break;
 731
 732                 case AE_CTRL_TERMINATE:
 733
 734                         status = AE_OK;
 735
 736                         /* Clean up */
 737                         do {
 738                                 if (op) {
 739                                         status2 =
 740                                             acpi_ps_complete_this_op(walk_state,
 741                                                                      op);
 742                                         if (ACPI_FAILURE(status2)) {
 743                                                 return_ACPI_STATUS(status2);
 744                                         }
 745                                 }
 746                                 acpi_ps_pop_scope(parser_state, &op,
 747                                                   &walk_state->arg_types,
 748                                                   &walk_state->arg_count);
 749
 750                         } while (op);
 751
 752                         return_ACPI_STATUS(status);
 753
 754                 default:        /* All other non-AE_OK status */
 755
 756                         do {
 757                                 if (op) {
 758                                         status2 =
 759                                             acpi_ps_complete_this_op(walk_state,
 760                                                                      op);
 761                                         if (ACPI_FAILURE(status2)) {
 762                                                 return_ACPI_STATUS(status2);
 763                                         }
 764                                 }
 765                                 acpi_ps_pop_scope(parser_state, &op,
 766                                                   &walk_state->arg_types,
 767                                                   &walk_state->arg_count);
 768
 769                         } while (op);
 770
 771                         /*
 772                          * TBD: Cleanup parse ops on error
 773                          */
 774 #if 0
 775                         if (op == NULL) {
 776                                 acpi_ps_pop_scope(parser_state, &op,
 777                                                   &walk_state->arg_types,
 778                                                   &walk_state->arg_count);
 779                         }
 780 #endif
 781                         walk_state->prev_op = op;
 782                         walk_state->prev_arg_types = walk_state->arg_types;
 783                         return_ACPI_STATUS(status);
 784                 }
 785
 786                 /* This scope complete? */
 787
 788                 if (acpi_ps_has_completed_scope(parser_state)) {
 789                         acpi_ps_pop_scope(parser_state, &op,
 790                                           &walk_state->arg_types,
 791                                           &walk_state->arg_count);
 792                         ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
 793                                           "Popped scope, Op=%p\n", op));
 794                 } else {
 795                         op = NULL;
 796                 }
 797
 798         }                       /* while parser_state->Aml */
 799
 800         /*
 801          * Complete the last Op (if not completed), and clear the scope stack.
 802          * It is easily possible to end an AML "package" with an unbounded number
 803          * of open scopes (such as when several ASL blocks are closed with
 804          * sequential closing braces).  We want to terminate each one cleanly.
 805          */
 806         ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "AML package complete at Op %p\n",
 807                           op));
 808         do {
 809                 if (op) {
 810                         if (walk_state->ascending_callback != NULL) {
 811                                 walk_state->op = op;
 812                                 walk_state->op_info =
 813                                     acpi_ps_get_opcode_info(op->common.
 814                                                             aml_opcode);
 815                                 walk_state->opcode = op->common.aml_opcode;
 816
 817                                 status =
 818                                     walk_state->ascending_callback(walk_state);
 819                                 status =
 820                                     acpi_ps_next_parse_state(walk_state, op,
 821                                                              status);
 822                                 if (status == AE_CTRL_PENDING) {
 823                                         status = AE_OK;
 824                                         goto close_this_op;
 825                                 }
 826
 827                                 if (status == AE_CTRL_TERMINATE) {
 828                                         status = AE_OK;
 829
 830                                         /* Clean up */
 831                                         do {
 832                                                 if (op) {
 833                                                         status2 =
 834                                                             acpi_ps_complete_this_op
 835                                                             (walk_state, op);
 836                                                         if (ACPI_FAILURE
 837                                                             (status2)) {
 838                                                                 return_ACPI_STATUS
 839                                                                     (status2);
 840                                                         }
 841                                                 }
 842
 843                                                 acpi_ps_pop_scope(parser_state,
 844                                                                   &op,
 845                                                                   &walk_state->
 846                                                                   arg_types,
 847                                                                   &walk_state->
 848                                                                   arg_count);
 849
 850                                         } while (op);
 851
 852                                         return_ACPI_STATUS(status);
 853                                 }
 854
 855                                 else if (ACPI_FAILURE(status)) {
 856                                         /* First error is most important */
 857
 858                                         (void)
 859                                             acpi_ps_complete_this_op(walk_state,
 860                                                                      op);
 861                                         return_ACPI_STATUS(status);
 862                                 }
 863                         }
 864
 865                         status2 = acpi_ps_complete_this_op(walk_state, op);
 866                         if (ACPI_FAILURE(status2)) {
 867                                 return_ACPI_STATUS(status2);
 868                         }
 869                 }
 870
 871                 acpi_ps_pop_scope(parser_state, &op, &walk_state->arg_types,
 872                                   &walk_state->arg_count);
 873
 874         } while (op);
 875
 876         return_ACPI_STATUS(status);
 877 }