git.oblomov.eu Git - linux-2.6/blob - 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
  99                 /* We are restarting a preempted control method */
 100
 101                 if (acpi_ps_has_completed_scope(parser_state)) {
 102                         /*
 103                          * We must check if a predicate to an IF or WHILE statement
 104                          * was just completed
 105                          */
 106                         if ((parser_state->scope->parse_scope.op) &&
 107                             ((parser_state->scope->parse_scope.op->common.
 108                               aml_opcode == AML_IF_OP)
 109                              || (parser_state->scope->parse_scope.op->common.
 110                                  aml_opcode == AML_WHILE_OP))
 111                             && (walk_state->control_state)
 112                             && (walk_state->control_state->common.state ==
 113                                 ACPI_CONTROL_PREDICATE_EXECUTING)) {
 114                                 /*
 115                                  * A predicate was just completed, get the value of the
 116                                  * predicate and branch based on that value
 117                                  */
 118                                 walk_state->op = NULL;
 119                                 status =
 120                                     acpi_ds_get_predicate_value(walk_state,
 121                                                                 ACPI_TO_POINTER
 122                                                                 (TRUE));
 123                                 if (ACPI_FAILURE(status)
 124                                     && ((status & AE_CODE_MASK) !=
 125                                         AE_CODE_CONTROL)) {
 126                                         if (status == AE_AML_NO_RETURN_VALUE) {
 127                                                 ACPI_EXCEPTION((AE_INFO, status,
 128                                                                 "Invoked method did not return a value"));
 129
 130                                         }
 131                                         ACPI_EXCEPTION((AE_INFO, status,
 132                                                         "get_predicate Failed"));
 133                                         return_ACPI_STATUS(status);
 134                                 }
 135
 136                                 status =
 137                                     acpi_ps_next_parse_state(walk_state, op,
 138                                                              status);
 139                         }
 140
 141                         acpi_ps_pop_scope(parser_state, &op,
 142                                           &walk_state->arg_types,
 143                                           &walk_state->arg_count);
 144                         ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
 145                                           "Popped scope, Op=%p\n", op));
 146                 } else if (walk_state->prev_op) {
 147
 148                         /* We were in the middle of an op */
 149
 150                         op = walk_state->prev_op;
 151                         walk_state->arg_types = walk_state->prev_arg_types;
 152                 }
 153         }
 154 #endif
 155
 156         /* Iterative parsing loop, while there is more AML to process: */
 157
 158         while ((parser_state->aml < parser_state->aml_end) || (op)) {
 159                 aml_op_start = parser_state->aml;
 160                 if (!op) {
 161
 162                         /* Get the next opcode from the AML stream */
 163
 164                         walk_state->aml_offset =
 165                             (u32) ACPI_PTR_DIFF(parser_state->aml,
 166                                                 parser_state->aml_start);
 167                         walk_state->opcode = acpi_ps_peek_opcode(parser_state);
 168
 169                         /*
 170                          * First cut to determine what we have found:
 171                          * 1) A valid AML opcode
 172                          * 2) A name string
 173                          * 3) An unknown/invalid opcode
 174                          */
 175                         walk_state->op_info =
 176                             acpi_ps_get_opcode_info(walk_state->opcode);
 177                         switch (walk_state->op_info->class) {
 178                         case AML_CLASS_ASCII:
 179                         case AML_CLASS_PREFIX:
 180                                 /*
 181                                  * Starts with a valid prefix or ASCII char, this is a name
 182                                  * string.  Convert the bare name string to a namepath.
 183                                  */
 184                                 walk_state->opcode = AML_INT_NAMEPATH_OP;
 185                                 walk_state->arg_types = ARGP_NAMESTRING;
 186                                 break;
 187
 188                         case AML_CLASS_UNKNOWN:
 189
 190                                 /* The opcode is unrecognized.  Just skip unknown opcodes */
 191
 192                                 ACPI_ERROR((AE_INFO,
 193                                             "Found unknown opcode %X at AML address %p offset %X, ignoring",
 194                                             walk_state->opcode,
 195                                             parser_state->aml,
 196                                             walk_state->aml_offset));
 197
 198                                 ACPI_DUMP_BUFFER(parser_state->aml, 128);
 199
 200                                 /* Assume one-byte bad opcode */
 201
 202                                 parser_state->aml++;
 203                                 continue;
 204
 205                         default:
 206
 207                                 /* Found opcode info, this is a normal opcode */
 208
 209                                 parser_state->aml +=
 210                                     acpi_ps_get_opcode_size(walk_state->opcode);
 211                                 walk_state->arg_types =
 212                                     walk_state->op_info->parse_args;
 213                                 break;
 214                         }
 215
 216                         /* Create Op structure and append to parent's argument list */
 217
 218                         if (walk_state->op_info->flags & AML_NAMED) {
 219
 220                                 /* Allocate a new pre_op if necessary */
 221
 222                                 if (!pre_op) {
 223                                         pre_op =
 224                                             acpi_ps_alloc_op(walk_state->
 225                                                              opcode);
 226                                         if (!pre_op) {
 227                                                 status = AE_NO_MEMORY;
 228                                                 goto close_this_op;
 229                                         }
 230                                 }
 231
 232                                 pre_op->common.value.arg = NULL;
 233                                 pre_op->common.aml_opcode = walk_state->opcode;
 234
 235                                 /*
 236                                  * Get and append arguments until we find the node that contains
 237                                  * the name (the type ARGP_NAME).
 238                                  */
 239                                 while (GET_CURRENT_ARG_TYPE
 240                                        (walk_state->arg_types)
 241                                        &&
 242                                        (GET_CURRENT_ARG_TYPE
 243                                         (walk_state->arg_types) != ARGP_NAME)) {
 244                                         status =
 245                                             acpi_ps_get_next_arg(walk_state,
 246                                                                  parser_state,
 247                                                                  GET_CURRENT_ARG_TYPE
 248                                                                  (walk_state->
 249                                                                   arg_types),
 250                                                                  &arg);
 251                                         if (ACPI_FAILURE(status)) {
 252                                                 goto close_this_op;
 253                                         }
 254
 255                                         acpi_ps_append_arg(pre_op, arg);
 256                                         INCREMENT_ARG_LIST(walk_state->
 257                                                            arg_types);
 258                                 }
 259
 260                                 /*
 261                                  * Make sure that we found a NAME and didn't run out of
 262                                  * arguments
 263                                  */
 264                                 if (!GET_CURRENT_ARG_TYPE
 265                                     (walk_state->arg_types)) {
 266                                         status = AE_AML_NO_OPERAND;
 267                                         goto close_this_op;
 268                                 }
 269
 270                                 /* We know that this arg is a name, move to next arg */
 271
 272                                 INCREMENT_ARG_LIST(walk_state->arg_types);
 273
 274                                 /*
 275                                  * Find the object.  This will either insert the object into
 276                                  * the namespace or simply look it up
 277                                  */
 278                                 walk_state->op = NULL;
 279
 280                                 status =
 281                                     walk_state->descending_callback(walk_state,
 282                                                                     &op);
 283                                 if (ACPI_FAILURE(status)) {
 284                                         ACPI_EXCEPTION((AE_INFO, status,
 285                                                         "During name lookup/catalog"));
 286                                         goto close_this_op;
 287                                 }
 288
 289                                 if (!op) {
 290                                         continue;
 291                                 }
 292
 293                                 status =
 294                                     acpi_ps_next_parse_state(walk_state, op,
 295                                                              status);
 296                                 if (status == AE_CTRL_PENDING) {
 297                                         status = AE_OK;
 298                                         goto close_this_op;
 299                                 }
 300
 301                                 if (ACPI_FAILURE(status)) {
 302                                         goto close_this_op;
 303                                 }
 304
 305                                 acpi_ps_append_arg(op,
 306                                                    pre_op->common.value.arg);
 307                                 acpi_gbl_depth++;
 308
 309                                 if (op->common.aml_opcode == AML_REGION_OP) {
 310                                         /*
 311                                          * Defer final parsing of an operation_region body,
 312                                          * because we don't have enough info in the first pass
 313                                          * to parse it correctly (i.e., there may be method
 314                                          * calls within the term_arg elements of the body.)
 315                                          *
 316                                          * However, we must continue parsing because
 317                                          * the opregion is not a standalone package --
 318                                          * we don't know where the end is at this point.
 319                                          *
 320                                          * (Length is unknown until parse of the body complete)
 321                                          */
 322                                         op->named.data = aml_op_start;
 323                                         op->named.length = 0;
 324                                 }
 325                         } else {
 326                                 /* Not a named opcode, just allocate Op and append to parent */
 327
 328                                 walk_state->op_info =
 329                                     acpi_ps_get_opcode_info(walk_state->opcode);
 330                                 op = acpi_ps_alloc_op(walk_state->opcode);
 331                                 if (!op) {
 332                                         status = AE_NO_MEMORY;
 333                                         goto close_this_op;
 334                                 }
 335
 336                                 if (walk_state->op_info->flags & AML_CREATE) {
 337                                         /*
 338                                          * Backup to beginning of create_xXXfield declaration
 339                                          * body_length is unknown until we parse the body
 340                                          */
 341                                         op->named.data = aml_op_start;
 342                                         op->named.length = 0;
 343                                 }
 344
 345                                 acpi_ps_append_arg(acpi_ps_get_parent_scope
 346                                                    (parser_state), op);
 347
 348                                 if ((walk_state->descending_callback != NULL)) {
 349                                         /*
 350                                          * Find the object. This will either insert the object into
 351                                          * the namespace or simply look it up
 352                                          */
 353                                         walk_state->op = op;
 354
 355                                         status =
 356                                             walk_state->
 357                                             descending_callback(walk_state,
 358                                                                 &op);
 359                                         status =
 360                                             acpi_ps_next_parse_state(walk_state,
 361                                                                      op,
 362                                                                      status);
 363                                         if (status == AE_CTRL_PENDING) {
 364                                                 status = AE_OK;
 365                                                 goto close_this_op;
 366                                         }
 367
 368                                         if (ACPI_FAILURE(status)) {
 369                                                 goto close_this_op;
 370                                         }
 371                                 }
 372                         }
 373
 374                         op->common.aml_offset = walk_state->aml_offset;
 375
 376                         if (walk_state->op_info) {
 377                                 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
 378                                                   "Opcode %4.4X [%s] Op %p Aml %p aml_offset %5.5X\n",
 379                                                   (u32) op->common.aml_opcode,
 380                                                   walk_state->op_info->name, op,
 381                                                   parser_state->aml,
 382                                                   op->common.aml_offset));
 383                         }
 384                 }
 385
 386                 /*
 387                  * Start arg_count at zero because we don't know if there are
 388                  * any args yet
 389                  */
 390                 walk_state->arg_count = 0;
 391
 392                 /* Are there any arguments that must be processed? */
 393
 394                 if (walk_state->arg_types) {
 395
 396                         /* Get arguments */
 397
 398                         switch (op->common.aml_opcode) {
 399                         case AML_BYTE_OP:       /* AML_BYTEDATA_ARG */
 400                         case AML_WORD_OP:       /* AML_WORDDATA_ARG */
 401                         case AML_DWORD_OP:      /* AML_DWORDATA_ARG */
 402                         case AML_QWORD_OP:      /* AML_QWORDATA_ARG */
 403                         case AML_STRING_OP:     /* AML_ASCIICHARLIST_ARG */
 404
 405                                 /* Fill in constant or string argument directly */
 406
 407                                 acpi_ps_get_next_simple_arg(parser_state,
 408                                                             GET_CURRENT_ARG_TYPE
 409                                                             (walk_state->
 410                                                              arg_types), op);
 411                                 break;
 412
 413                         case AML_INT_NAMEPATH_OP:       /* AML_NAMESTRING_ARG */
 414
 415                                 status =
 416                                     acpi_ps_get_next_namepath(walk_state,
 417                                                               parser_state, op,
 418                                                               1);
 419                                 if (ACPI_FAILURE(status)) {
 420                                         goto close_this_op;
 421                                 }
 422
 423                                 walk_state->arg_types = 0;
 424                                 break;
 425
 426                         default:
 427                                 /*
 428                                  * Op is not a constant or string, append each argument
 429                                  * to the Op
 430                                  */
 431                                 while (GET_CURRENT_ARG_TYPE
 432                                        (walk_state->arg_types)
 433                                        && !walk_state->arg_count) {
 434                                         walk_state->aml_offset = (u32)
 435                                             ACPI_PTR_DIFF(parser_state->aml,
 436                                                           parser_state->
 437                                                           aml_start);
 438
 439                                         status =
 440                                             acpi_ps_get_next_arg(walk_state,
 441                                                                  parser_state,
 442                                                                  GET_CURRENT_ARG_TYPE
 443                                                                  (walk_state->
 444                                                                   arg_types),
 445                                                                  &arg);
 446                                         if (ACPI_FAILURE(status)) {
 447                                                 goto close_this_op;
 448                                         }
 449
 450                                         if (arg) {
 451                                                 arg->common.aml_offset =
 452                                                     walk_state->aml_offset;
 453                                                 acpi_ps_append_arg(op, arg);
 454                                         }
 455                                         INCREMENT_ARG_LIST(walk_state->
 456                                                            arg_types);
 457                                 }
 458
 459                                 /* Special processing for certain opcodes */
 460
 461                                 /* TBD (remove): Temporary mechanism to disable this code if needed */
 462
 463 #ifdef ACPI_ENABLE_MODULE_LEVEL_CODE
 464
 465                                 if ((walk_state->pass_number <=
 466                                      ACPI_IMODE_LOAD_PASS1)
 467                                     &&
 468                                     ((walk_state->
 469                                       parse_flags & ACPI_PARSE_DISASSEMBLE) ==
 470                                      0)) {
 471                                         /*
 472                                          * We want to skip If/Else/While constructs during Pass1
 473                                          * because we want to actually conditionally execute the
 474                                          * code during Pass2.
 475                                          *
 476                                          * Except for disassembly, where we always want to
 477                                          * walk the If/Else/While packages
 478                                          */
 479                                         switch (op->common.aml_opcode) {
 480                                         case AML_IF_OP:
 481                                         case AML_ELSE_OP:
 482                                         case AML_WHILE_OP:
 483
 484                                                 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
 485                                                                   "Pass1: Skipping an If/Else/While body\n"));
 486
 487                                                 /* Skip body of if/else/while in pass 1 */
 488
 489                                                 parser_state->aml =
 490                                                     parser_state->pkg_end;
 491                                                 walk_state->arg_count = 0;
 492                                                 break;
 493
 494                                         default:
 495                                                 break;
 496                                         }
 497                                 }
 498 #endif
 499                                 switch (op->common.aml_opcode) {
 500                                 case AML_METHOD_OP:
 501
 502                                         /*
 503                                          * Skip parsing of control method
 504                                          * because we don't have enough info in the first pass
 505                                          * to parse it correctly.
 506                                          *
 507                                          * Save the length and address of the body
 508                                          */
 509                                         op->named.data = parser_state->aml;
 510                                         op->named.length =
 511                                             (u32) (parser_state->pkg_end -
 512                                                    parser_state->aml);
 513
 514                                         /* Skip body of method */
 515
 516                                         parser_state->aml =
 517                                             parser_state->pkg_end;
 518                                         walk_state->arg_count = 0;
 519                                         break;
 520
 521                                 case AML_BUFFER_OP:
 522                                 case AML_PACKAGE_OP:
 523                                 case AML_VAR_PACKAGE_OP:
 524
 525                                         if ((op->common.parent) &&
 526                                             (op->common.parent->common.
 527                                              aml_opcode == AML_NAME_OP)
 528                                             && (walk_state->pass_number <=
 529                                                 ACPI_IMODE_LOAD_PASS2)) {
 530                                                 /*
 531                                                  * Skip parsing of Buffers and Packages
 532                                                  * because we don't have enough info in the first pass
 533                                                  * to parse them correctly.
 534                                                  */
 535                                                 op->named.data = aml_op_start;
 536                                                 op->named.length =
 537                                                     (u32) (parser_state->
 538                                                            pkg_end -
 539                                                            aml_op_start);
 540
 541                                                 /* Skip body */
 542
 543                                                 parser_state->aml =
 544                                                     parser_state->pkg_end;
 545                                                 walk_state->arg_count = 0;
 546                                         }
 547                                         break;
 548
 549                                 case AML_WHILE_OP:
 550
 551                                         if (walk_state->control_state) {
 552                                                 walk_state->control_state->
 553                                                     control.package_end =
 554                                                     parser_state->pkg_end;
 555                                         }
 556                                         break;
 557
 558                                 default:
 559
 560                                         /* No action for all other opcodes */
 561                                         break;
 562                                 }
 563                                 break;
 564                         }
 565                 }
 566
 567                 /* Check for arguments that need to be processed */
 568
 569                 if (walk_state->arg_count) {
 570                         /*
 571                          * There are arguments (complex ones), push Op and
 572                          * prepare for argument
 573                          */
 574                         status = acpi_ps_push_scope(parser_state, op,
 575                                                     walk_state->arg_types,
 576                                                     walk_state->arg_count);
 577                         if (ACPI_FAILURE(status)) {
 578                                 goto close_this_op;
 579                         }
 580                         op = NULL;
 581                         continue;
 582                 }
 583
 584                 /*
 585                  * All arguments have been processed -- Op is complete,
 586                  * prepare for next
 587                  */
 588                 walk_state->op_info =
 589                     acpi_ps_get_opcode_info(op->common.aml_opcode);
 590                 if (walk_state->op_info->flags & AML_NAMED) {
 591                         if (acpi_gbl_depth) {
 592                                 acpi_gbl_depth--;
 593                         }
 594
 595                         if (op->common.aml_opcode == AML_REGION_OP) {
 596                                 /*
 597                                  * Skip parsing of control method or opregion body,
 598                                  * because we don't have enough info in the first pass
 599                                  * to parse them correctly.
 600                                  *
 601                                  * Completed parsing an op_region declaration, we now
 602                                  * know the length.
 603                                  */
 604                                 op->named.length =
 605                                     (u32) (parser_state->aml - op->named.data);
 606                         }
 607                 }
 608
 609                 if (walk_state->op_info->flags & AML_CREATE) {
 610                         /*
 611                          * Backup to beginning of create_xXXfield declaration (1 for
 612                          * Opcode)
 613                          *
 614                          * body_length is unknown until we parse the body
 615                          */
 616                         op->named.length =
 617                             (u32) (parser_state->aml - op->named.data);
 618                 }
 619
 620                 /* This op complete, notify the dispatcher */
 621
 622                 if (walk_state->ascending_callback != NULL) {
 623                         walk_state->op = op;
 624                         walk_state->opcode = op->common.aml_opcode;
 625
 626                         status = walk_state->ascending_callback(walk_state);
 627                         status =
 628                             acpi_ps_next_parse_state(walk_state, op, status);
 629                         if (status == AE_CTRL_PENDING) {
 630                                 status = AE_OK;
 631                                 goto close_this_op;
 632                         }
 633                 }
 634
 635               close_this_op:
 636                 /*
 637                  * Finished one argument of the containing scope
 638                  */
 639                 parser_state->scope->parse_scope.arg_count--;
 640
 641                 /* Finished with pre_op */
 642
 643                 if (pre_op) {
 644                         acpi_ps_free_op(pre_op);
 645                         pre_op = NULL;
 646                 }
 647
 648                 /* Close this Op (will result in parse subtree deletion) */
 649
 650                 status2 = acpi_ps_complete_this_op(walk_state, op);
 651                 if (ACPI_FAILURE(status2)) {
 652                         return_ACPI_STATUS(status2);
 653                 }
 654                 op = NULL;
 655
 656                 switch (status) {
 657                 case AE_OK:
 658                         break;
 659
 660                 case AE_CTRL_TRANSFER:
 661
 662                         /* We are about to transfer to a called method. */
 663
 664                         walk_state->prev_op = op;
 665                         walk_state->prev_arg_types = walk_state->arg_types;
 666                         return_ACPI_STATUS(status);
 667
 668                 case AE_CTRL_END:
 669
 670                         acpi_ps_pop_scope(parser_state, &op,
 671                                           &walk_state->arg_types,
 672                                           &walk_state->arg_count);
 673
 674                         if (op) {
 675                                 walk_state->op = op;
 676                                 walk_state->op_info =
 677                                     acpi_ps_get_opcode_info(op->common.
 678                                                             aml_opcode);
 679                                 walk_state->opcode = op->common.aml_opcode;
 680
 681                                 status =
 682                                     walk_state->ascending_callback(walk_state);
 683                                 status =
 684                                     acpi_ps_next_parse_state(walk_state, op,
 685                                                              status);
 686
 687                                 status2 =
 688                                     acpi_ps_complete_this_op(walk_state, op);
 689                                 if (ACPI_FAILURE(status2)) {
 690                                         return_ACPI_STATUS(status2);
 691                                 }
 692                                 op = NULL;
 693                         }
 694                         status = AE_OK;
 695                         break;
 696
 697                 case AE_CTRL_BREAK:
 698                 case AE_CTRL_CONTINUE:
 699
 700                         /* Pop off scopes until we find the While */
 701
 702                         while (!op || (op->common.aml_opcode != AML_WHILE_OP)) {
 703                                 acpi_ps_pop_scope(parser_state, &op,
 704                                                   &walk_state->arg_types,
 705                                                   &walk_state->arg_count);
 706
 707                                 if (op->common.aml_opcode != AML_WHILE_OP) {
 708                                         status2 =
 709                                             acpi_ds_result_stack_pop
 710                                             (walk_state);
 711                                         if (ACPI_FAILURE(status2)) {
 712                                                 return_ACPI_STATUS(status2);
 713                                         }
 714                                 }
 715                         }
 716
 717                         /* Close this iteration of the While loop */
 718
 719                         walk_state->op = op;
 720                         walk_state->op_info =
 721                             acpi_ps_get_opcode_info(op->common.aml_opcode);
 722                         walk_state->opcode = op->common.aml_opcode;
 723
 724                         status = walk_state->ascending_callback(walk_state);
 725                         status =
 726                             acpi_ps_next_parse_state(walk_state, op, status);
 727
 728                         status2 = acpi_ps_complete_this_op(walk_state, op);
 729                         if (ACPI_FAILURE(status2)) {
 730                                 return_ACPI_STATUS(status2);
 731                         }
 732                         op = NULL;
 733
 734                         status = AE_OK;
 735                         break;
 736
 737                 case AE_CTRL_TERMINATE:
 738
 739                         status = AE_OK;
 740
 741                         /* Clean up */
 742                         do {
 743                                 if (op) {
 744                                         status2 =
 745                                             acpi_ps_complete_this_op(walk_state,
 746                                                                      op);
 747                                         if (ACPI_FAILURE(status2)) {
 748                                                 return_ACPI_STATUS(status2);
 749                                         }
 750                                 }
 751                                 acpi_ps_pop_scope(parser_state, &op,
 752                                                   &walk_state->arg_types,
 753                                                   &walk_state->arg_count);
 754
 755                         } while (op);
 756
 757                         return_ACPI_STATUS(status);
 758
 759                 default:        /* All other non-AE_OK status */
 760
 761                         do {
 762                                 if (op) {
 763                                         status2 =
 764                                             acpi_ps_complete_this_op(walk_state,
 765                                                                      op);
 766                                         if (ACPI_FAILURE(status2)) {
 767                                                 return_ACPI_STATUS(status2);
 768                                         }
 769                                 }
 770
 771                                 acpi_ps_pop_scope(parser_state, &op,
 772                                                   &walk_state->arg_types,
 773                                                   &walk_state->arg_count);
 774
 775                         } while (op);
 776
 777                         /*
 778                          * TBD: Cleanup parse ops on error
 779                          */
 780 #if 0
 781                         if (op == NULL) {
 782                                 acpi_ps_pop_scope(parser_state, &op,
 783                                                   &walk_state->arg_types,
 784                                                   &walk_state->arg_count);
 785                         }
 786 #endif
 787                         walk_state->prev_op = op;
 788                         walk_state->prev_arg_types = walk_state->arg_types;
 789                         return_ACPI_STATUS(status);
 790                 }
 791
 792                 /* This scope complete? */
 793
 794                 if (acpi_ps_has_completed_scope(parser_state)) {
 795                         acpi_ps_pop_scope(parser_state, &op,
 796                                           &walk_state->arg_types,
 797                                           &walk_state->arg_count);
 798                         ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
 799                                           "Popped scope, Op=%p\n", op));
 800                 } else {
 801                         op = NULL;
 802                 }
 803
 804         }                       /* while parser_state->Aml */
 805
 806         /*
 807          * Complete the last Op (if not completed), and clear the scope stack.
 808          * It is easily possible to end an AML "package" with an unbounded number
 809          * of open scopes (such as when several ASL blocks are closed with
 810          * sequential closing braces).  We want to terminate each one cleanly.
 811          */
 812         ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "AML package complete at Op %p\n",
 813                           op));
 814         do {
 815                 if (op) {
 816                         if (walk_state->ascending_callback != NULL) {
 817                                 walk_state->op = op;
 818                                 walk_state->op_info =
 819                                     acpi_ps_get_opcode_info(op->common.
 820                                                             aml_opcode);
 821                                 walk_state->opcode = op->common.aml_opcode;
 822
 823                                 status =
 824                                     walk_state->ascending_callback(walk_state);
 825                                 status =
 826                                     acpi_ps_next_parse_state(walk_state, op,
 827                                                              status);
 828                                 if (status == AE_CTRL_PENDING) {
 829                                         status = AE_OK;
 830                                         goto close_this_op;
 831                                 }
 832
 833                                 if (status == AE_CTRL_TERMINATE) {
 834                                         status = AE_OK;
 835
 836                                         /* Clean up */
 837                                         do {
 838                                                 if (op) {
 839                                                         status2 =
 840                                                             acpi_ps_complete_this_op
 841                                                             (walk_state, op);
 842                                                         if (ACPI_FAILURE
 843                                                             (status2)) {
 844                                                                 return_ACPI_STATUS
 845                                                                     (status2);
 846                                                         }
 847                                                 }
 848
 849                                                 acpi_ps_pop_scope(parser_state,
 850                                                                   &op,
 851                                                                   &walk_state->
 852                                                                   arg_types,
 853                                                                   &walk_state->
 854                                                                   arg_count);
 855
 856                                         } while (op);
 857
 858                                         return_ACPI_STATUS(status);
 859                                 }
 860
 861                                 else if (ACPI_FAILURE(status)) {
 862
 863                                         /* First error is most important */
 864
 865                                         (void)
 866                                             acpi_ps_complete_this_op(walk_state,
 867                                                                      op);
 868                                         return_ACPI_STATUS(status);
 869                                 }
 870                         }
 871
 872                         status2 = acpi_ps_complete_this_op(walk_state, op);
 873                         if (ACPI_FAILURE(status2)) {
 874                                 return_ACPI_STATUS(status2);
 875                         }
 876                 }
 877
 878                 acpi_ps_pop_scope(parser_state, &op, &walk_state->arg_types,
 879                                   &walk_state->arg_count);
 880
 881         } while (op);
 882
 883         return_ACPI_STATUS(status);
 884 }