err.no 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 - 2007, R. Byron Moore
   9  * All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions, and the following disclaimer,
  16  *    without modification.
  17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  18  *    substantially similar to the "NO WARRANTY" disclaimer below
  19  *    ("Disclaimer") and any redistribution must be conditioned upon
  20  *    including a substantially similar Disclaimer requirement for further
  21  *    binary redistribution.
  22  * 3. Neither the names of the above-listed copyright holders nor the names
  23  *    of any contributors may be used to endorse or promote products derived
  24  *    from this software without specific prior written permission.
  25  *
  26  * Alternatively, this software may be distributed under the terms of the
  27  * GNU General Public License ("GPL") version 2 as published by the Free
  28  * Software Foundation.
  29  *
  30  * NO WARRANTY
  31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  41  * POSSIBILITY OF SUCH DAMAGES.
  42  */
  43
  44 /*
  45  * Parse the AML and build an operation tree as most interpreters, (such as
  46  * Perl) do. Parsing is done by hand rather than with a YACC generated parser
  47  * to tightly constrain stack and dynamic memory usage. Parsing is kept
  48  * flexible and the code fairly compact by parsing based on a list of AML
  49  * opcode templates in aml_op_info[].
  50  */
  51
  52 #include <acpi/acpi.h>
  53 #include <acpi/acparser.h>
  54 #include <acpi/acdispat.h>
  55 #include <acpi/amlcode.h>
  56
  57 #define _COMPONENT          ACPI_PARSER
  58 ACPI_MODULE_NAME("psloop")
  59
  60 static u32 acpi_gbl_depth = 0;
  61
  62 /* Local prototypes */
  63
  64 static acpi_status acpi_ps_get_aml_opcode(struct acpi_walk_state *walk_state);
  65
  66 static acpi_status
  67 acpi_ps_build_named_op(struct acpi_walk_state *walk_state,
  68                        u8 * aml_op_start,
  69                        union acpi_parse_object *unnamed_op,
  70                        union acpi_parse_object **op);
  71
  72 static acpi_status
  73 acpi_ps_create_op(struct acpi_walk_state *walk_state,
  74                   u8 * aml_op_start, union acpi_parse_object **new_op);
  75
  76 static acpi_status
  77 acpi_ps_get_arguments(struct acpi_walk_state *walk_state,
  78                       u8 * aml_op_start, union acpi_parse_object *op);
  79
  80 static acpi_status
  81 acpi_ps_complete_op(struct acpi_walk_state *walk_state,
  82                     union acpi_parse_object **op, acpi_status status);
  83
  84 static acpi_status
  85 acpi_ps_complete_final_op(struct acpi_walk_state *walk_state,
  86                           union acpi_parse_object *op, acpi_status status);
  87
  88 /*******************************************************************************
  89  *
  90  * FUNCTION:    acpi_ps_get_aml_opcode
  91  *
  92  * PARAMETERS:  walk_state          - Current state
  93  *
  94  * RETURN:      Status
  95  *
  96  * DESCRIPTION: Extract the next AML opcode from the input stream.
  97  *
  98  ******************************************************************************/
  99
 100 static acpi_status acpi_ps_get_aml_opcode(struct acpi_walk_state *walk_state)
 101 {
 102
 103         ACPI_FUNCTION_TRACE_PTR(ps_get_aml_opcode, walk_state);
 104
 105         walk_state->aml_offset =
 106             (u32) ACPI_PTR_DIFF(walk_state->parser_state.aml,
 107                                 walk_state->parser_state.aml_start);
 108         walk_state->opcode = acpi_ps_peek_opcode(&(walk_state->parser_state));
 109
 110         /*
 111          * First cut to determine what we have found:
 112          * 1) A valid AML opcode
 113          * 2) A name string
 114          * 3) An unknown/invalid opcode
 115          */
 116         walk_state->op_info = acpi_ps_get_opcode_info(walk_state->opcode);
 117
 118         switch (walk_state->op_info->class) {
 119         case AML_CLASS_ASCII:
 120         case AML_CLASS_PREFIX:
 121                 /*
 122                  * Starts with a valid prefix or ASCII char, this is a name
 123                  * string. Convert the bare name string to a namepath.
 124                  */
 125                 walk_state->opcode = AML_INT_NAMEPATH_OP;
 126                 walk_state->arg_types = ARGP_NAMESTRING;
 127                 break;
 128
 129         case AML_CLASS_UNKNOWN:
 130
 131                 /* The opcode is unrecognized. Just skip unknown opcodes */
 132
 133                 ACPI_ERROR((AE_INFO,
 134                             "Found unknown opcode %X at AML address %p offset %X, ignoring",
 135                             walk_state->opcode, walk_state->parser_state.aml,
 136                             walk_state->aml_offset));
 137
 138                 ACPI_DUMP_BUFFER(walk_state->parser_state.aml, 128);
 139
 140                 /* Assume one-byte bad opcode */
 141
 142                 walk_state->parser_state.aml++;
 143                 return_ACPI_STATUS(AE_CTRL_PARSE_CONTINUE);
 144
 145         default:
 146
 147                 /* Found opcode info, this is a normal opcode */
 148
 149                 walk_state->parser_state.aml +=
 150                     acpi_ps_get_opcode_size(walk_state->opcode);
 151                 walk_state->arg_types = walk_state->op_info->parse_args;
 152                 break;
 153         }
 154
 155         return_ACPI_STATUS(AE_OK);
 156 }
 157
 158 /*******************************************************************************
 159  *
 160  * FUNCTION:    acpi_ps_build_named_op
 161  *
 162  * PARAMETERS:  walk_state          - Current state
 163  *              aml_op_start        - Begin of named Op in AML
 164  *              unnamed_op          - Early Op (not a named Op)
 165  *              Op                  - Returned Op
 166  *
 167  * RETURN:      Status
 168  *
 169  * DESCRIPTION: Parse a named Op
 170  *
 171  ******************************************************************************/
 172
 173 static acpi_status
 174 acpi_ps_build_named_op(struct acpi_walk_state *walk_state,
 175                        u8 * aml_op_start,
 176                        union acpi_parse_object *unnamed_op,
 177                        union acpi_parse_object **op)
 178 {
 179         acpi_status status = AE_OK;
 180         union acpi_parse_object *arg = NULL;
 181
 182         ACPI_FUNCTION_TRACE_PTR(ps_build_named_op, walk_state);
 183
 184         unnamed_op->common.value.arg = NULL;
 185         unnamed_op->common.aml_opcode = walk_state->opcode;
 186
 187         /*
 188          * Get and append arguments until we find the node that contains
 189          * the name (the type ARGP_NAME).
 190          */
 191         while (GET_CURRENT_ARG_TYPE(walk_state->arg_types) &&
 192                (GET_CURRENT_ARG_TYPE(walk_state->arg_types) != ARGP_NAME)) {
 193                 status =
 194                     acpi_ps_get_next_arg(walk_state,
 195                                          &(walk_state->parser_state),
 196                                          GET_CURRENT_ARG_TYPE(walk_state->
 197                                                               arg_types), &arg);
 198                 if (ACPI_FAILURE(status)) {
 199                         return_ACPI_STATUS(status);
 200                 }
 201
 202                 acpi_ps_append_arg(unnamed_op, arg);
 203                 INCREMENT_ARG_LIST(walk_state->arg_types);
 204         }
 205
 206         /*
 207          * Make sure that we found a NAME and didn't run out of arguments
 208          */
 209         if (!GET_CURRENT_ARG_TYPE(walk_state->arg_types)) {
 210                 return_ACPI_STATUS(AE_AML_NO_OPERAND);
 211         }
 212
 213         /* We know that this arg is a name, move to next arg */
 214
 215         INCREMENT_ARG_LIST(walk_state->arg_types);
 216
 217         /*
 218          * Find the object. This will either insert the object into
 219          * the namespace or simply look it up
 220          */
 221         walk_state->op = NULL;
 222
 223         status = walk_state->descending_callback(walk_state, op);
 224         if (ACPI_FAILURE(status)) {
 225                 ACPI_EXCEPTION((AE_INFO, status, "During name lookup/catalog"));
 226                 return_ACPI_STATUS(status);
 227         }
 228
 229         if (!*op) {
 230                 return_ACPI_STATUS(AE_CTRL_PARSE_CONTINUE);
 231         }
 232
 233         status = acpi_ps_next_parse_state(walk_state, *op, status);
 234         if (ACPI_FAILURE(status)) {
 235                 if (status == AE_CTRL_PENDING) {
 236                         return_ACPI_STATUS(AE_CTRL_PARSE_PENDING);
 237                 }
 238                 return_ACPI_STATUS(status);
 239         }
 240
 241         acpi_ps_append_arg(*op, unnamed_op->common.value.arg);
 242         acpi_gbl_depth++;
 243
 244         if ((*op)->common.aml_opcode == AML_REGION_OP) {
 245                 /*
 246                  * Defer final parsing of an operation_region body, because we don't
 247                  * have enough info in the first pass to parse it correctly (i.e.,
 248                  * there may be method calls within the term_arg elements of the body.)
 249                  *
 250                  * However, we must continue parsing because the opregion is not a
 251                  * standalone package -- we don't know where the end is at this point.
 252                  *
 253                  * (Length is unknown until parse of the body complete)
 254                  */
 255                 (*op)->named.data = aml_op_start;
 256                 (*op)->named.length = 0;
 257         }
 258
 259         return_ACPI_STATUS(AE_OK);
 260 }
 261
 262 /*******************************************************************************
 263  *
 264  * FUNCTION:    acpi_ps_create_op
 265  *
 266  * PARAMETERS:  walk_state          - Current state
 267  *              aml_op_start        - Op start in AML
 268  *              new_op              - Returned Op
 269  *
 270  * RETURN:      Status
 271  *
 272  * DESCRIPTION: Get Op from AML
 273  *
 274  ******************************************************************************/
 275
 276 static acpi_status
 277 acpi_ps_create_op(struct acpi_walk_state *walk_state,
 278                   u8 * aml_op_start, union acpi_parse_object **new_op)
 279 {
 280         acpi_status status = AE_OK;
 281         union acpi_parse_object *op;
 282         union acpi_parse_object *named_op = NULL;
 283
 284         ACPI_FUNCTION_TRACE_PTR(ps_create_op, walk_state);
 285
 286         status = acpi_ps_get_aml_opcode(walk_state);
 287         if (status == AE_CTRL_PARSE_CONTINUE) {
 288                 return_ACPI_STATUS(AE_CTRL_PARSE_CONTINUE);
 289         }
 290
 291         /* Create Op structure and append to parent's argument list */
 292
 293         walk_state->op_info = acpi_ps_get_opcode_info(walk_state->opcode);
 294         op = acpi_ps_alloc_op(walk_state->opcode);
 295         if (!op) {
 296                 return_ACPI_STATUS(AE_NO_MEMORY);
 297         }
 298
 299         if (walk_state->op_info->flags & AML_NAMED) {
 300                 status =
 301                     acpi_ps_build_named_op(walk_state, aml_op_start, op,
 302                                            &named_op);
 303                 acpi_ps_free_op(op);
 304                 if (ACPI_FAILURE(status)) {
 305                         return_ACPI_STATUS(status);
 306                 }
 307
 308                 *new_op = named_op;
 309                 return_ACPI_STATUS(AE_OK);
 310         }
 311
 312         /* Not a named opcode, just allocate Op and append to parent */
 313
 314         if (walk_state->op_info->flags & AML_CREATE) {
 315                 /*
 316                  * Backup to beginning of create_xXXfield declaration
 317                  * body_length is unknown until we parse the body
 318                  */
 319                 op->named.data = aml_op_start;
 320                 op->named.length = 0;
 321         }
 322
 323         acpi_ps_append_arg(acpi_ps_get_parent_scope
 324                            (&(walk_state->parser_state)), op);
 325
 326         if (walk_state->descending_callback != NULL) {
 327                 /*
 328                  * Find the object. This will either insert the object into
 329                  * the namespace or simply look it up
 330                  */
 331                 walk_state->op = *new_op = op;
 332
 333                 status = walk_state->descending_callback(walk_state, &op);
 334                 status = acpi_ps_next_parse_state(walk_state, op, status);
 335                 if (status == AE_CTRL_PENDING) {
 336                         status = AE_CTRL_PARSE_PENDING;
 337                 }
 338         }
 339
 340         return_ACPI_STATUS(status);
 341 }
 342
 343 /*******************************************************************************
 344  *
 345  * FUNCTION:    acpi_ps_get_arguments
 346  *
 347  * PARAMETERS:  walk_state          - Current state
 348  *              aml_op_start        - Op start in AML
 349  *              Op                  - Current Op
 350  *
 351  * RETURN:      Status
 352  *
 353  * DESCRIPTION: Get arguments for passed Op.
 354  *
 355  ******************************************************************************/
 356
 357 static acpi_status
 358 acpi_ps_get_arguments(struct acpi_walk_state *walk_state,
 359                       u8 * aml_op_start, union acpi_parse_object *op)
 360 {
 361         acpi_status status = AE_OK;
 362         union acpi_parse_object *arg = NULL;
 363
 364         ACPI_FUNCTION_TRACE_PTR(ps_get_arguments, walk_state);
 365
 366         switch (op->common.aml_opcode) {
 367         case AML_BYTE_OP:       /* AML_BYTEDATA_ARG */
 368         case AML_WORD_OP:       /* AML_WORDDATA_ARG */
 369         case AML_DWORD_OP:      /* AML_DWORDATA_ARG */
 370         case AML_QWORD_OP:      /* AML_QWORDATA_ARG */
 371         case AML_STRING_OP:     /* AML_ASCIICHARLIST_ARG */
 372
 373                 /* Fill in constant or string argument directly */
 374
 375                 acpi_ps_get_next_simple_arg(&(walk_state->parser_state),
 376                                             GET_CURRENT_ARG_TYPE(walk_state->
 377                                                                  arg_types),
 378                                             op);
 379                 break;
 380
 381         case AML_INT_NAMEPATH_OP:       /* AML_NAMESTRING_ARG */
 382
 383                 status =
 384                     acpi_ps_get_next_namepath(walk_state,
 385                                               &(walk_state->parser_state), op,
 386                                               1);
 387                 if (ACPI_FAILURE(status)) {
 388                         return_ACPI_STATUS(status);
 389                 }
 390
 391                 walk_state->arg_types = 0;
 392                 break;
 393
 394         default:
 395                 /*
 396                  * Op is not a constant or string, append each argument to the Op
 397                  */
 398                 while (GET_CURRENT_ARG_TYPE(walk_state->arg_types)
 399                        && !walk_state->arg_count) {
 400                         walk_state->aml_offset =
 401                             (u32) ACPI_PTR_DIFF(walk_state->parser_state.aml,
 402                                                 walk_state->parser_state.
 403                                                 aml_start);
 404
 405                         status =
 406                             acpi_ps_get_next_arg(walk_state,
 407                                                  &(walk_state->parser_state),
 408                                                  GET_CURRENT_ARG_TYPE
 409                                                  (walk_state->arg_types), &arg);
 410                         if (ACPI_FAILURE(status)) {
 411                                 return_ACPI_STATUS(status);
 412                         }
 413
 414                         if (arg) {
 415                                 arg->common.aml_offset = walk_state->aml_offset;
 416                                 acpi_ps_append_arg(op, arg);
 417                         }
 418
 419                         INCREMENT_ARG_LIST(walk_state->arg_types);
 420                 }
 421
 422                 /* Special processing for certain opcodes */
 423
 424                 /* TBD (remove): Temporary mechanism to disable this code if needed */
 425
 426 #ifdef ACPI_ENABLE_MODULE_LEVEL_CODE
 427
 428                 if ((walk_state->pass_number <= ACPI_IMODE_LOAD_PASS1) &&
 429                     ((walk_state->parse_flags & ACPI_PARSE_DISASSEMBLE) == 0)) {
 430                         /*
 431                          * We want to skip If/Else/While constructs during Pass1 because we
 432                          * want to actually conditionally execute the code during Pass2.
 433                          *
 434                          * Except for disassembly, where we always want to walk the
 435                          * If/Else/While packages
 436                          */
 437                         switch (op->common.aml_opcode) {
 438                         case AML_IF_OP:
 439                         case AML_ELSE_OP:
 440                         case AML_WHILE_OP:
 441
 442                                 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
 443                                                   "Pass1: Skipping an If/Else/While body\n"));
 444
 445                                 /* Skip body of if/else/while in pass 1 */
 446
 447                                 walk_state->parser_state.aml =
 448                                     walk_state->parser_state.pkg_end;
 449                                 walk_state->arg_count = 0;
 450                                 break;
 451
 452                         default:
 453                                 break;
 454                         }
 455                 }
 456 #endif
 457
 458                 switch (op->common.aml_opcode) {
 459                 case AML_METHOD_OP:
 460                         /*
 461                          * Skip parsing of control method because we don't have enough
 462                          * info in the first pass to parse it correctly.
 463                          *
 464                          * Save the length and address of the body
 465                          */
 466                         op->named.data = walk_state->parser_state.aml;
 467                         op->named.length = (u32)
 468                             (walk_state->parser_state.pkg_end -
 469                              walk_state->parser_state.aml);
 470
 471                         /* Skip body of method */
 472
 473                         walk_state->parser_state.aml =
 474                             walk_state->parser_state.pkg_end;
 475                         walk_state->arg_count = 0;
 476                         break;
 477
 478                 case AML_BUFFER_OP:
 479                 case AML_PACKAGE_OP:
 480                 case AML_VAR_PACKAGE_OP:
 481
 482                         if ((op->common.parent) &&
 483                             (op->common.parent->common.aml_opcode ==
 484                              AML_NAME_OP)
 485                             && (walk_state->pass_number <=
 486                                 ACPI_IMODE_LOAD_PASS2)) {
 487                                 /*
 488                                  * Skip parsing of Buffers and Packages because we don't have
 489                                  * enough info in the first pass to parse them correctly.
 490                                  */
 491                                 op->named.data = aml_op_start;
 492                                 op->named.length = (u32)
 493                                     (walk_state->parser_state.pkg_end -
 494                                      aml_op_start);
 495
 496                                 /* Skip body */
 497
 498                                 walk_state->parser_state.aml =
 499                                     walk_state->parser_state.pkg_end;
 500                                 walk_state->arg_count = 0;
 501                         }
 502                         break;
 503
 504                 case AML_WHILE_OP:
 505
 506                         if (walk_state->control_state) {
 507                                 walk_state->control_state->control.package_end =
 508                                     walk_state->parser_state.pkg_end;
 509                         }
 510                         break;
 511
 512                 default:
 513
 514                         /* No action for all other opcodes */
 515                         break;
 516                 }
 517
 518                 break;
 519         }
 520
 521         return_ACPI_STATUS(AE_OK);
 522 }
 523
 524 /*******************************************************************************
 525  *
 526  * FUNCTION:    acpi_ps_complete_op
 527  *
 528  * PARAMETERS:  walk_state          - Current state
 529  *              Op                  - Returned Op
 530  *              Status              - Parse status before complete Op
 531  *
 532  * RETURN:      Status
 533  *
 534  * DESCRIPTION: Complete Op
 535  *
 536  ******************************************************************************/
 537
 538 static acpi_status
 539 acpi_ps_complete_op(struct acpi_walk_state *walk_state,
 540                     union acpi_parse_object **op, acpi_status status)
 541 {
 542         acpi_status status2;
 543
 544         ACPI_FUNCTION_TRACE_PTR(ps_complete_op, walk_state);
 545
 546         /*
 547          * Finished one argument of the containing scope
 548          */
 549         walk_state->parser_state.scope->parse_scope.arg_count--;
 550
 551         /* Close this Op (will result in parse subtree deletion) */
 552
 553         status2 = acpi_ps_complete_this_op(walk_state, *op);
 554         if (ACPI_FAILURE(status2)) {
 555                 return_ACPI_STATUS(status2);
 556         }
 557
 558         *op = NULL;
 559
 560         switch (status) {
 561         case AE_OK:
 562                 break;
 563
 564         case AE_CTRL_TRANSFER:
 565
 566                 /* We are about to transfer to a called method */
 567
 568                 walk_state->prev_op = NULL;
 569                 walk_state->prev_arg_types = walk_state->arg_types;
 570                 return_ACPI_STATUS(status);
 571
 572         case AE_CTRL_END:
 573
 574                 acpi_ps_pop_scope(&(walk_state->parser_state), op,
 575                                   &walk_state->arg_types,
 576                                   &walk_state->arg_count);
 577
 578                 if (*op) {
 579                         walk_state->op = *op;
 580                         walk_state->op_info =
 581                             acpi_ps_get_opcode_info((*op)->common.aml_opcode);
 582                         walk_state->opcode = (*op)->common.aml_opcode;
 583
 584                         status = walk_state->ascending_callback(walk_state);
 585                         status =
 586                             acpi_ps_next_parse_state(walk_state, *op, status);
 587
 588                         status2 = acpi_ps_complete_this_op(walk_state, *op);
 589                         if (ACPI_FAILURE(status2)) {
 590                                 return_ACPI_STATUS(status2);
 591                         }
 592                 }
 593
 594                 status = AE_OK;
 595                 break;
 596
 597         case AE_CTRL_BREAK:
 598         case AE_CTRL_CONTINUE:
 599
 600                 /* Pop off scopes until we find the While */
 601
 602                 while (!(*op) || ((*op)->common.aml_opcode != AML_WHILE_OP)) {
 603                         acpi_ps_pop_scope(&(walk_state->parser_state), op,
 604                                           &walk_state->arg_types,
 605                                           &walk_state->arg_count);
 606
 607                         if ((*op)->common.aml_opcode != AML_WHILE_OP) {
 608                                 status2 = acpi_ds_result_stack_pop(walk_state);
 609                                 if (ACPI_FAILURE(status2)) {
 610                                         return_ACPI_STATUS(status2);
 611                                 }
 612                         }
 613                 }
 614
 615                 /* Close this iteration of the While loop */
 616
 617                 walk_state->op = *op;
 618                 walk_state->op_info =
 619                     acpi_ps_get_opcode_info((*op)->common.aml_opcode);
 620                 walk_state->opcode = (*op)->common.aml_opcode;
 621
 622                 status = walk_state->ascending_callback(walk_state);
 623                 status = acpi_ps_next_parse_state(walk_state, *op, status);
 624
 625                 status2 = acpi_ps_complete_this_op(walk_state, *op);
 626                 if (ACPI_FAILURE(status2)) {
 627                         return_ACPI_STATUS(status2);
 628                 }
 629
 630                 status = AE_OK;
 631                 break;
 632
 633         case AE_CTRL_TERMINATE:
 634
 635                 /* Clean up */
 636                 do {
 637                         if (*op) {
 638                                 status2 =
 639                                     acpi_ps_complete_this_op(walk_state, *op);
 640                                 if (ACPI_FAILURE(status2)) {
 641                                         return_ACPI_STATUS(status2);
 642                                 }
 643                                 status2 = acpi_ds_result_stack_pop(walk_state);
 644                                 if (ACPI_FAILURE(status2)) {
 645                                         return_ACPI_STATUS(status2);
 646                                 }
 647
 648                                 acpi_ut_delete_generic_state
 649                                     (acpi_ut_pop_generic_state
 650                                      (&walk_state->control_state));
 651                         }
 652
 653                         acpi_ps_pop_scope(&(walk_state->parser_state), op,
 654                                           &walk_state->arg_types,
 655                                           &walk_state->arg_count);
 656
 657                 } while (*op);
 658
 659                 return_ACPI_STATUS(AE_OK);
 660
 661         default:                /* All other non-AE_OK status */
 662
 663                 do {
 664                         if (*op) {
 665                                 status2 =
 666                                     acpi_ps_complete_this_op(walk_state, *op);
 667                                 if (ACPI_FAILURE(status2)) {
 668                                         return_ACPI_STATUS(status2);
 669                                 }
 670                         }
 671
 672                         acpi_ps_pop_scope(&(walk_state->parser_state), op,
 673                                           &walk_state->arg_types,
 674                                           &walk_state->arg_count);
 675
 676                 } while (*op);
 677
 678 #if 0
 679                 /*
 680                  * TBD: Cleanup parse ops on error
 681                  */
 682                 if (*op == NULL) {
 683                         acpi_ps_pop_scope(parser_state, op,
 684                                           &walk_state->arg_types,
 685                                           &walk_state->arg_count);
 686                 }
 687 #endif
 688                 walk_state->prev_op = NULL;
 689                 walk_state->prev_arg_types = walk_state->arg_types;
 690                 return_ACPI_STATUS(status);
 691         }
 692
 693         /* This scope complete? */
 694
 695         if (acpi_ps_has_completed_scope(&(walk_state->parser_state))) {
 696                 acpi_ps_pop_scope(&(walk_state->parser_state), op,
 697                                   &walk_state->arg_types,
 698                                   &walk_state->arg_count);
 699                 ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "Popped scope, Op=%p\n", *op));
 700         } else {
 701                 *op = NULL;
 702         }
 703
 704         return_ACPI_STATUS(AE_OK);
 705 }
 706
 707 /*******************************************************************************
 708  *
 709  * FUNCTION:    acpi_ps_complete_final_op
 710  *
 711  * PARAMETERS:  walk_state          - Current state
 712  *              Op                  - Current Op
 713  *              Status              - Current parse status before complete last
 714  *                                    Op
 715  *
 716  * RETURN:      Status
 717  *
 718  * DESCRIPTION: Complete last Op.
 719  *
 720  ******************************************************************************/
 721
 722 static acpi_status
 723 acpi_ps_complete_final_op(struct acpi_walk_state *walk_state,
 724                           union acpi_parse_object *op, acpi_status status)
 725 {
 726         acpi_status status2;
 727
 728         ACPI_FUNCTION_TRACE_PTR(ps_complete_final_op, walk_state);
 729
 730         /*
 731          * Complete the last Op (if not completed), and clear the scope stack.
 732          * It is easily possible to end an AML "package" with an unbounded number
 733          * of open scopes (such as when several ASL blocks are closed with
 734          * sequential closing braces). We want to terminate each one cleanly.
 735          */
 736         ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "AML package complete at Op %p\n",
 737                           op));
 738         do {
 739                 if (op) {
 740                         if (walk_state->ascending_callback != NULL) {
 741                                 walk_state->op = op;
 742                                 walk_state->op_info =
 743                                     acpi_ps_get_opcode_info(op->common.
 744                                                             aml_opcode);
 745                                 walk_state->opcode = op->common.aml_opcode;
 746
 747                                 status =
 748                                     walk_state->ascending_callback(walk_state);
 749                                 status =
 750                                     acpi_ps_next_parse_state(walk_state, op,
 751                                                              status);
 752                                 if (status == AE_CTRL_PENDING) {
 753                                         status =
 754                                             acpi_ps_complete_op(walk_state, &op,
 755                                                                 AE_OK);
 756                                         if (ACPI_FAILURE(status)) {
 757                                                 return_ACPI_STATUS(status);
 758                                         }
 759                                 }
 760
 761                                 if (status == AE_CTRL_TERMINATE) {
 762                                         status = AE_OK;
 763
 764                                         /* Clean up */
 765                                         do {
 766                                                 if (op) {
 767                                                         status2 =
 768                                                             acpi_ps_complete_this_op
 769                                                             (walk_state, op);
 770                                                         if (ACPI_FAILURE
 771                                                             (status2)) {
 772                                                                 return_ACPI_STATUS
 773                                                                     (status2);
 774                                                         }
 775                                                 }
 776
 777                                                 acpi_ps_pop_scope(&
 778                                                                   (walk_state->
 779                                                                    parser_state),
 780                                                                   &op,
 781                                                                   &walk_state->
 782                                                                   arg_types,
 783                                                                   &walk_state->
 784                                                                   arg_count);
 785
 786                                         } while (op);
 787
 788                                         return_ACPI_STATUS(status);
 789                                 }
 790
 791                                 else if (ACPI_FAILURE(status)) {
 792
 793                                         /* First error is most important */
 794
 795                                         (void)
 796                                             acpi_ps_complete_this_op(walk_state,
 797                                                                      op);
 798                                         return_ACPI_STATUS(status);
 799                                 }
 800                         }
 801
 802                         status2 = acpi_ps_complete_this_op(walk_state, op);
 803                         if (ACPI_FAILURE(status2)) {
 804                                 return_ACPI_STATUS(status2);
 805                         }
 806                 }
 807
 808                 acpi_ps_pop_scope(&(walk_state->parser_state), &op,
 809                                   &walk_state->arg_types,
 810                                   &walk_state->arg_count);
 811
 812         } while (op);
 813
 814         return_ACPI_STATUS(status);
 815 }
 816
 817 /*******************************************************************************
 818  *
 819  * FUNCTION:    acpi_ps_parse_loop
 820  *
 821  * PARAMETERS:  walk_state          - Current state
 822  *
 823  * RETURN:      Status
 824  *
 825  * DESCRIPTION: Parse AML (pointed to by the current parser state) and return
 826  *              a tree of ops.
 827  *
 828  ******************************************************************************/
 829
 830 acpi_status acpi_ps_parse_loop(struct acpi_walk_state *walk_state)
 831 {
 832         acpi_status status = AE_OK;
 833         union acpi_parse_object *op = NULL;     /* current op */
 834         struct acpi_parse_state *parser_state;
 835         u8 *aml_op_start = NULL;
 836
 837         ACPI_FUNCTION_TRACE_PTR(ps_parse_loop, walk_state);
 838
 839         if (walk_state->descending_callback == NULL) {
 840                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 841         }
 842
 843         parser_state = &walk_state->parser_state;
 844         walk_state->arg_types = 0;
 845
 846 #if (!defined (ACPI_NO_METHOD_EXECUTION) && !defined (ACPI_CONSTANT_EVAL_ONLY))
 847
 848         if (walk_state->walk_type & ACPI_WALK_METHOD_RESTART) {
 849
 850                 /* We are restarting a preempted control method */
 851
 852                 if (acpi_ps_has_completed_scope(parser_state)) {
 853                         /*
 854                          * We must check if a predicate to an IF or WHILE statement
 855                          * was just completed
 856                          */
 857                         if ((parser_state->scope->parse_scope.op) &&
 858                             ((parser_state->scope->parse_scope.op->common.
 859                               aml_opcode == AML_IF_OP)
 860                              || (parser_state->scope->parse_scope.op->common.
 861                                  aml_opcode == AML_WHILE_OP))
 862                             && (walk_state->control_state)
 863                             && (walk_state->control_state->common.state ==
 864                                 ACPI_CONTROL_PREDICATE_EXECUTING)) {
 865                                 /*
 866                                  * A predicate was just completed, get the value of the
 867                                  * predicate and branch based on that value
 868                                  */
 869                                 walk_state->op = NULL;
 870                                 status =
 871                                     acpi_ds_get_predicate_value(walk_state,
 872                                                                 ACPI_TO_POINTER
 873                                                                 (TRUE));
 874                                 if (ACPI_FAILURE(status)
 875                                     && ((status & AE_CODE_MASK) !=
 876                                         AE_CODE_CONTROL)) {
 877                                         if (status == AE_AML_NO_RETURN_VALUE) {
 878                                                 ACPI_EXCEPTION((AE_INFO, status,
 879                                                                 "Invoked method did not return a value"));
 880
 881                                         }
 882
 883                                         ACPI_EXCEPTION((AE_INFO, status,
 884                                                         "GetPredicate Failed"));
 885                                         return_ACPI_STATUS(status);
 886                                 }
 887
 888                                 status =
 889                                     acpi_ps_next_parse_state(walk_state, op,
 890                                                              status);
 891                         }
 892
 893                         acpi_ps_pop_scope(parser_state, &op,
 894                                           &walk_state->arg_types,
 895                                           &walk_state->arg_count);
 896                         ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
 897                                           "Popped scope, Op=%p\n", op));
 898                 } else if (walk_state->prev_op) {
 899
 900                         /* We were in the middle of an op */
 901
 902                         op = walk_state->prev_op;
 903                         walk_state->arg_types = walk_state->prev_arg_types;
 904                 }
 905         }
 906 #endif
 907
 908         /* Iterative parsing loop, while there is more AML to process: */
 909
 910         while ((parser_state->aml < parser_state->aml_end) || (op)) {
 911                 aml_op_start = parser_state->aml;
 912                 if (!op) {
 913                         status =
 914                             acpi_ps_create_op(walk_state, aml_op_start, &op);
 915                         if (ACPI_FAILURE(status)) {
 916                                 if (status == AE_CTRL_PARSE_CONTINUE) {
 917                                         continue;
 918                                 }
 919
 920                                 if (status == AE_CTRL_PARSE_PENDING) {
 921                                         status = AE_OK;
 922                                 }
 923
 924                                 status =
 925                                     acpi_ps_complete_op(walk_state, &op,
 926                                                         status);
 927                                 if (ACPI_FAILURE(status)) {
 928                                         return_ACPI_STATUS(status);
 929                                 }
 930
 931                                 continue;
 932                         }
 933
 934                         op->common.aml_offset = walk_state->aml_offset;
 935
 936                         if (walk_state->op_info) {
 937                                 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
 938                                                   "Opcode %4.4X [%s] Op %p Aml %p AmlOffset %5.5X\n",
 939                                                   (u32) op->common.aml_opcode,
 940                                                   walk_state->op_info->name, op,
 941                                                   parser_state->aml,
 942                                                   op->common.aml_offset));
 943                         }
 944                 }
 945
 946                 /*
 947                  * Start arg_count at zero because we don't know if there are
 948                  * any args yet
 949                  */
 950                 walk_state->arg_count = 0;
 951
 952                 /* Are there any arguments that must be processed? */
 953
 954                 if (walk_state->arg_types) {
 955
 956                         /* Get arguments */
 957
 958                         status =
 959                             acpi_ps_get_arguments(walk_state, aml_op_start, op);
 960                         if (ACPI_FAILURE(status)) {
 961                                 status =
 962                                     acpi_ps_complete_op(walk_state, &op,
 963                                                         status);
 964                                 if (ACPI_FAILURE(status)) {
 965                                         return_ACPI_STATUS(status);
 966                                 }
 967
 968                                 continue;
 969                         }
 970                 }
 971
 972                 /* Check for arguments that need to be processed */
 973
 974                 if (walk_state->arg_count) {
 975                         /*
 976                          * There are arguments (complex ones), push Op and
 977                          * prepare for argument
 978                          */
 979                         status = acpi_ps_push_scope(parser_state, op,
 980                                                     walk_state->arg_types,
 981                                                     walk_state->arg_count);
 982                         if (ACPI_FAILURE(status)) {
 983                                 status =
 984                                     acpi_ps_complete_op(walk_state, &op,
 985                                                         status);
 986                                 if (ACPI_FAILURE(status)) {
 987                                         return_ACPI_STATUS(status);
 988                                 }
 989
 990                                 continue;
 991                         }
 992
 993                         op = NULL;
 994                         continue;
 995                 }
 996
 997                 /*
 998                  * All arguments have been processed -- Op is complete,
 999                  * prepare for next
1000                  */
1001                 walk_state->op_info =
1002                     acpi_ps_get_opcode_info(op->common.aml_opcode);
1003                 if (walk_state->op_info->flags & AML_NAMED) {
1004                         if (acpi_gbl_depth) {
1005                                 acpi_gbl_depth--;
1006                         }
1007
1008                         if (op->common.aml_opcode == AML_REGION_OP) {
1009                                 /*
1010                                  * Skip parsing of control method or opregion body,
1011                                  * because we don't have enough info in the first pass
1012                                  * to parse them correctly.
1013                                  *
1014                                  * Completed parsing an op_region declaration, we now
1015                                  * know the length.
1016                                  */
1017                                 op->named.length =
1018                                     (u32) (parser_state->aml - op->named.data);
1019                         }
1020                 }
1021
1022                 if (walk_state->op_info->flags & AML_CREATE) {
1023                         /*
1024                          * Backup to beginning of create_xXXfield declaration (1 for
1025                          * Opcode)
1026                          *
1027                          * body_length is unknown until we parse the body
1028                          */
1029                         op->named.length =
1030                             (u32) (parser_state->aml - op->named.data);
1031                 }
1032
1033                 /* This op complete, notify the dispatcher */
1034
1035                 if (walk_state->ascending_callback != NULL) {
1036                         walk_state->op = op;
1037                         walk_state->opcode = op->common.aml_opcode;
1038
1039                         status = walk_state->ascending_callback(walk_state);
1040                         status =
1041                             acpi_ps_next_parse_state(walk_state, op, status);
1042                         if (status == AE_CTRL_PENDING) {
1043                                 status = AE_OK;
1044                         }
1045                 }
1046
1047                 status = acpi_ps_complete_op(walk_state, &op, status);
1048                 if (ACPI_FAILURE(status)) {
1049                         return_ACPI_STATUS(status);
1050                 }
1051
1052         }                       /* while parser_state->Aml */
1053
1054         status = acpi_ps_complete_final_op(walk_state, op, status);
1055         return_ACPI_STATUS(status);
1056 }