drivers/acpi/dispatcher/dsutils.c

   1 /*******************************************************************************
   2  *
   3  * Module Name: dsutils - Dispatcher utilities
   4  *
   5  ******************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2005, R. Byron Moore
   9  * All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions, and the following disclaimer,
  16  *    without modification.
  17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  18  *    substantially similar to the "NO WARRANTY" disclaimer below
  19  *    ("Disclaimer") and any redistribution must be conditioned upon
  20  *    including a substantially similar Disclaimer requirement for further
  21  *    binary redistribution.
  22  * 3. Neither the names of the above-listed copyright holders nor the names
  23  *    of any contributors may be used to endorse or promote products derived
  24  *    from this software without specific prior written permission.
  25  *
  26  * Alternatively, this software may be distributed under the terms of the
  27  * GNU General Public License ("GPL") version 2 as published by the Free
  28  * Software Foundation.
  29  *
  30  * NO WARRANTY
  31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  41  * POSSIBILITY OF SUCH DAMAGES.
  42  */
  43
  44
  45 #include <acpi/acpi.h>
  46 #include <acpi/acparser.h>
  47 #include <acpi/amlcode.h>
  48 #include <acpi/acdispat.h>
  49 #include <acpi/acinterp.h>
  50 #include <acpi/acnamesp.h>
  51 #include <acpi/acdebug.h>
  52
  53 #define _COMPONENT          ACPI_DISPATCHER
  54          ACPI_MODULE_NAME    ("dsutils")
  55
  56
  57 /*******************************************************************************
  58  *
  59  * FUNCTION:    acpi_ds_clear_implicit_return
  60  *
  61  * PARAMETERS:  walk_state          - Current State
  62  *
  63  * RETURN:      None.
  64  *
  65  * DESCRIPTION: Clear and remove a reference on an implicit return value.  Used
  66  *              to delete "stale" return values (if enabled, the return value
  67  *              from every operator is saved at least momentarily, in case the
  68  *              parent method exits.)
  69  *
  70  ******************************************************************************/
  71
  72 void
  73 acpi_ds_clear_implicit_return (
  74         struct acpi_walk_state          *walk_state)
  75 {
  76         ACPI_FUNCTION_NAME ("ds_clear_implicit_return");
  77
  78
  79         /*
  80          * Slack must be enabled for this feature
  81          */
  82         if (!acpi_gbl_enable_interpreter_slack) {
  83                 return;
  84         }
  85
  86         if (walk_state->implicit_return_obj) {
  87                 /*
  88                  * Delete any "stale" implicit return. However, in
  89                  * complex statements, the implicit return value can be
  90                  * bubbled up several levels.
  91                  */
  92                 ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
  93                         "Removing reference on stale implicit return obj %p\n",
  94                         walk_state->implicit_return_obj));
  95
  96                 acpi_ut_remove_reference (walk_state->implicit_return_obj);
  97                 walk_state->implicit_return_obj = NULL;
  98         }
  99 }
 100
 101
 102 #ifndef ACPI_NO_METHOD_EXECUTION
 103
 104 /*******************************************************************************
 105  *
 106  * FUNCTION:    acpi_ds_do_implicit_return
 107  *
 108  * PARAMETERS:  return_desc         - The return value
 109  *              walk_state          - Current State
 110  *              add_reference       - True if a reference should be added to the
 111  *                                    return object
 112  *
 113  * RETURN:      TRUE if implicit return enabled, FALSE otherwise
 114  *
 115  * DESCRIPTION: Implements the optional "implicit return".  We save the result
 116  *              of every ASL operator and control method invocation in case the
 117  *              parent method exit.  Before storing a new return value, we
 118  *              delete the previous return value.
 119  *
 120  ******************************************************************************/
 121
 122 u8
 123 acpi_ds_do_implicit_return (
 124         union acpi_operand_object       *return_desc,
 125         struct acpi_walk_state          *walk_state,
 126         u8                              add_reference)
 127 {
 128         ACPI_FUNCTION_NAME ("ds_do_implicit_return");
 129
 130
 131         /*
 132          * Slack must be enabled for this feature, and we must
 133          * have a valid return object
 134          */
 135         if ((!acpi_gbl_enable_interpreter_slack) ||
 136                 (!return_desc)) {
 137                 return (FALSE);
 138         }
 139
 140         ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
 141                         "Result %p will be implicitly returned; Prev=%p\n",
 142                         return_desc,
 143                         walk_state->implicit_return_obj));
 144
 145         /*
 146          * Delete any "stale" implicit return value first. However, in
 147          * complex statements, the implicit return value can be
 148          * bubbled up several levels, so we don't clear the value if it
 149          * is the same as the return_desc.
 150          */
 151         if (walk_state->implicit_return_obj) {
 152                 if (walk_state->implicit_return_obj == return_desc) {
 153                         return (TRUE);
 154                 }
 155                 acpi_ds_clear_implicit_return (walk_state);
 156         }
 157
 158         /* Save the implicit return value, add a reference if requested */
 159
 160         walk_state->implicit_return_obj = return_desc;
 161         if (add_reference) {
 162                 acpi_ut_add_reference (return_desc);
 163         }
 164
 165         return (TRUE);
 166 }
 167
 168
 169 /*******************************************************************************
 170  *
 171  * FUNCTION:    acpi_ds_is_result_used
 172  *
 173  * PARAMETERS:  Op                  - Current Op
 174  *              walk_state          - Current State
 175  *
 176  * RETURN:      TRUE if result is used, FALSE otherwise
 177  *
 178  * DESCRIPTION: Check if a result object will be used by the parent
 179  *
 180  ******************************************************************************/
 181
 182 u8
 183 acpi_ds_is_result_used (
 184         union acpi_parse_object         *op,
 185         struct acpi_walk_state          *walk_state)
 186 {
 187         const struct acpi_opcode_info   *parent_info;
 188
 189         ACPI_FUNCTION_TRACE_PTR ("ds_is_result_used", op);
 190
 191
 192         /* Must have both an Op and a Result Object */
 193
 194         if (!op) {
 195                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Null Op\n"));
 196                 return_VALUE (TRUE);
 197         }
 198
 199         /*
 200          * We know that this operator is not a
 201          * Return() operator (would not come here.) The following code is the
 202          * optional support for a so-called "implicit return". Some AML code
 203          * assumes that the last value of the method is "implicitly" returned
 204          * to the caller. Just save the last result as the return value.
 205          * NOTE: this is optional because the ASL language does not actually
 206          * support this behavior.
 207          */
 208         acpi_ds_do_implicit_return (walk_state->result_obj, walk_state, TRUE);
 209
 210         /*
 211          * Now determine if the parent will use the result
 212          *
 213          * If there is no parent, or the parent is a scope_op, we are executing
 214          * at the method level. An executing method typically has no parent,
 215          * since each method is parsed separately.  A method invoked externally
 216          * via execute_control_method has a scope_op as the parent.
 217          */
 218         if ((!op->common.parent) ||
 219                 (op->common.parent->common.aml_opcode == AML_SCOPE_OP)) {
 220                 /* No parent, the return value cannot possibly be used */
 221
 222                 ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "At Method level, result of [%s] not used\n",
 223                                 acpi_ps_get_opcode_name (op->common.aml_opcode)));
 224                 return_VALUE (FALSE);
 225         }
 226
 227         /* Get info on the parent. The root_op is AML_SCOPE */
 228
 229         parent_info = acpi_ps_get_opcode_info (op->common.parent->common.aml_opcode);
 230         if (parent_info->class == AML_CLASS_UNKNOWN) {
 231                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Unknown parent opcode. Op=%p\n", op));
 232                 return_VALUE (FALSE);
 233         }
 234
 235         /*
 236          * Decide what to do with the result based on the parent.  If
 237          * the parent opcode will not use the result, delete the object.
 238          * Otherwise leave it as is, it will be deleted when it is used
 239          * as an operand later.
 240          */
 241         switch (parent_info->class) {
 242         case AML_CLASS_CONTROL:
 243
 244                 switch (op->common.parent->common.aml_opcode) {
 245                 case AML_RETURN_OP:
 246
 247                         /* Never delete the return value associated with a return opcode */
 248
 249                         goto result_used;
 250
 251                 case AML_IF_OP:
 252                 case AML_WHILE_OP:
 253
 254                         /*
 255                          * If we are executing the predicate AND this is the predicate op,
 256                          * we will use the return value
 257                          */
 258                         if ((walk_state->control_state->common.state == ACPI_CONTROL_PREDICATE_EXECUTING) &&
 259                                 (walk_state->control_state->control.predicate_op == op)) {
 260                                 goto result_used;
 261                         }
 262                         break;
 263
 264                 default:
 265                         /* Ignore other control opcodes */
 266                         break;
 267                 }
 268
 269                 /* The general control opcode returns no result */
 270
 271                 goto result_not_used;
 272
 273
 274         case AML_CLASS_CREATE:
 275
 276                 /*
 277                  * These opcodes allow term_arg(s) as operands and therefore
 278                  * the operands can be method calls.  The result is used.
 279                  */
 280                 goto result_used;
 281
 282
 283         case AML_CLASS_NAMED_OBJECT:
 284
 285                 if ((op->common.parent->common.aml_opcode == AML_REGION_OP)      ||
 286                         (op->common.parent->common.aml_opcode == AML_DATA_REGION_OP) ||
 287                         (op->common.parent->common.aml_opcode == AML_PACKAGE_OP)     ||
 288                         (op->common.parent->common.aml_opcode == AML_VAR_PACKAGE_OP) ||
 289                         (op->common.parent->common.aml_opcode == AML_BUFFER_OP)      ||
 290                         (op->common.parent->common.aml_opcode == AML_INT_EVAL_SUBTREE_OP)) {
 291                         /*
 292                          * These opcodes allow term_arg(s) as operands and therefore
 293                          * the operands can be method calls.  The result is used.
 294                          */
 295                         goto result_used;
 296                 }
 297
 298                 goto result_not_used;
 299
 300
 301         default:
 302
 303                 /*
 304                  * In all other cases. the parent will actually use the return
 305                  * object, so keep it.
 306                  */
 307                 goto result_used;
 308         }
 309
 310
 311 result_used:
 312         ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "Result of [%s] used by Parent [%s] Op=%p\n",
 313                         acpi_ps_get_opcode_name (op->common.aml_opcode),
 314                         acpi_ps_get_opcode_name (op->common.parent->common.aml_opcode), op));
 315
 316         return_VALUE (TRUE);
 317
 318
 319 result_not_used:
 320         ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "Result of [%s] not used by Parent [%s] Op=%p\n",
 321                         acpi_ps_get_opcode_name (op->common.aml_opcode),
 322                         acpi_ps_get_opcode_name (op->common.parent->common.aml_opcode), op));
 323
 324         return_VALUE (FALSE);
 325 }
 326
 327
 328 /*******************************************************************************
 329  *
 330  * FUNCTION:    acpi_ds_delete_result_if_not_used
 331  *
 332  * PARAMETERS:  Op              - Current parse Op
 333  *              result_obj      - Result of the operation
 334  *              walk_state      - Current state
 335  *
 336  * RETURN:      Status
 337  *
 338  * DESCRIPTION: Used after interpretation of an opcode.  If there is an internal
 339  *              result descriptor, check if the parent opcode will actually use
 340  *              this result.  If not, delete the result now so that it will
 341  *              not become orphaned.
 342  *
 343  ******************************************************************************/
 344
 345 void
 346 acpi_ds_delete_result_if_not_used (
 347         union acpi_parse_object         *op,
 348         union acpi_operand_object       *result_obj,
 349         struct acpi_walk_state          *walk_state)
 350 {
 351         union acpi_operand_object       *obj_desc;
 352         acpi_status                     status;
 353
 354
 355         ACPI_FUNCTION_TRACE_PTR ("ds_delete_result_if_not_used", result_obj);
 356
 357
 358         if (!op) {
 359                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Null Op\n"));
 360                 return_VOID;
 361         }
 362
 363         if (!result_obj) {
 364                 return_VOID;
 365         }
 366
 367         if (!acpi_ds_is_result_used (op, walk_state)) {
 368                 /* Must pop the result stack (obj_desc should be equal to result_obj) */
 369
 370                 status = acpi_ds_result_pop (&obj_desc, walk_state);
 371                 if (ACPI_SUCCESS (status)) {
 372                         acpi_ut_remove_reference (result_obj);
 373                 }
 374         }
 375
 376         return_VOID;
 377 }
 378
 379
 380 /*******************************************************************************
 381  *
 382  * FUNCTION:    acpi_ds_resolve_operands
 383  *
 384  * PARAMETERS:  walk_state          - Current walk state with operands on stack
 385  *
 386  * RETURN:      Status
 387  *
 388  * DESCRIPTION: Resolve all operands to their values.  Used to prepare
 389  *              arguments to a control method invocation (a call from one
 390  *              method to another.)
 391  *
 392  ******************************************************************************/
 393
 394 acpi_status
 395 acpi_ds_resolve_operands (
 396         struct acpi_walk_state          *walk_state)
 397 {
 398         u32                             i;
 399         acpi_status                     status = AE_OK;
 400
 401
 402         ACPI_FUNCTION_TRACE_PTR ("ds_resolve_operands", walk_state);
 403
 404
 405         /*
 406          * Attempt to resolve each of the valid operands
 407          * Method arguments are passed by reference, not by value.  This means
 408          * that the actual objects are passed, not copies of the objects.
 409          */
 410         for (i = 0; i < walk_state->num_operands; i++) {
 411                 status = acpi_ex_resolve_to_value (&walk_state->operands[i], walk_state);
 412                 if (ACPI_FAILURE (status)) {
 413                         break;
 414                 }
 415         }
 416
 417         return_ACPI_STATUS (status);
 418 }
 419
 420
 421 /*******************************************************************************
 422  *
 423  * FUNCTION:    acpi_ds_clear_operands
 424  *
 425  * PARAMETERS:  walk_state          - Current walk state with operands on stack
 426  *
 427  * RETURN:      None
 428  *
 429  * DESCRIPTION: Clear all operands on the current walk state operand stack.
 430  *
 431  ******************************************************************************/
 432
 433 void
 434 acpi_ds_clear_operands (
 435         struct acpi_walk_state          *walk_state)
 436 {
 437         u32                             i;
 438
 439
 440         ACPI_FUNCTION_TRACE_PTR ("ds_clear_operands", walk_state);
 441
 442
 443         /* Remove a reference on each operand on the stack */
 444
 445         for (i = 0; i < walk_state->num_operands; i++) {
 446                 /*
 447                  * Remove a reference to all operands, including both
 448                  * "Arguments" and "Targets".
 449                  */
 450                 acpi_ut_remove_reference (walk_state->operands[i]);
 451                 walk_state->operands[i] = NULL;
 452         }
 453
 454         walk_state->num_operands = 0;
 455         return_VOID;
 456 }
 457 #endif
 458
 459
 460 /*******************************************************************************
 461  *
 462  * FUNCTION:    acpi_ds_create_operand
 463  *
 464  * PARAMETERS:  walk_state      - Current walk state
 465  *              Arg             - Parse object for the argument
 466  *              arg_index       - Which argument (zero based)
 467  *
 468  * RETURN:      Status
 469  *
 470  * DESCRIPTION: Translate a parse tree object that is an argument to an AML
 471  *              opcode to the equivalent interpreter object.  This may include
 472  *              looking up a name or entering a new name into the internal
 473  *              namespace.
 474  *
 475  ******************************************************************************/
 476
 477 acpi_status
 478 acpi_ds_create_operand (
 479         struct acpi_walk_state          *walk_state,
 480         union acpi_parse_object         *arg,
 481         u32                             arg_index)
 482 {
 483         acpi_status                     status = AE_OK;
 484         char                            *name_string;
 485         u32                             name_length;
 486         union acpi_operand_object       *obj_desc;
 487         union acpi_parse_object         *parent_op;
 488         u16                             opcode;
 489         acpi_interpreter_mode           interpreter_mode;
 490         const struct acpi_opcode_info   *op_info;
 491
 492
 493         ACPI_FUNCTION_TRACE_PTR ("ds_create_operand", arg);
 494
 495
 496         /* A valid name must be looked up in the namespace */
 497
 498         if ((arg->common.aml_opcode == AML_INT_NAMEPATH_OP) &&
 499                 (arg->common.value.string)) {
 500                 ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "Getting a name: Arg=%p\n", arg));
 501
 502                 /* Get the entire name string from the AML stream */
 503
 504                 status = acpi_ex_get_name_string (ACPI_TYPE_ANY, arg->common.value.buffer,
 505                                   &name_string, &name_length);
 506
 507                 if (ACPI_FAILURE (status)) {
 508                         return_ACPI_STATUS (status);
 509                 }
 510
 511                 /* All prefixes have been handled, and the name is in name_string */
 512
 513                 /*
 514                  * Special handling for buffer_field declarations. This is a deferred
 515                  * opcode that unfortunately defines the field name as the last
 516                  * parameter instead of the first.  We get here when we are performing
 517                  * the deferred execution, so the actual name of the field is already
 518                  * in the namespace.  We don't want to attempt to look it up again
 519                  * because we may be executing in a different scope than where the
 520                  * actual opcode exists.
 521                  */
 522                 if ((walk_state->deferred_node) &&
 523                         (walk_state->deferred_node->type == ACPI_TYPE_BUFFER_FIELD) &&
 524                         (arg_index != 0)) {
 525                         obj_desc = ACPI_CAST_PTR (union acpi_operand_object, walk_state->deferred_node);
 526                         status = AE_OK;
 527                 }
 528                 else    /* All other opcodes */ {
 529                         /*
 530                          * Differentiate between a namespace "create" operation
 531                          * versus a "lookup" operation (IMODE_LOAD_PASS2 vs.
 532                          * IMODE_EXECUTE) in order to support the creation of
 533                          * namespace objects during the execution of control methods.
 534                          */
 535                         parent_op = arg->common.parent;
 536                         op_info = acpi_ps_get_opcode_info (parent_op->common.aml_opcode);
 537                         if ((op_info->flags & AML_NSNODE) &&
 538                                 (parent_op->common.aml_opcode != AML_INT_METHODCALL_OP) &&
 539                                 (parent_op->common.aml_opcode != AML_REGION_OP) &&
 540                                 (parent_op->common.aml_opcode != AML_INT_NAMEPATH_OP)) {
 541                                 /* Enter name into namespace if not found */
 542
 543                                 interpreter_mode = ACPI_IMODE_LOAD_PASS2;
 544                         }
 545                         else {
 546                                 /* Return a failure if name not found */
 547
 548                                 interpreter_mode = ACPI_IMODE_EXECUTE;
 549                         }
 550
 551                         status = acpi_ns_lookup (walk_state->scope_info, name_string,
 552                                          ACPI_TYPE_ANY, interpreter_mode,
 553                                          ACPI_NS_SEARCH_PARENT | ACPI_NS_DONT_OPEN_SCOPE,
 554                                          walk_state,
 555                                          ACPI_CAST_INDIRECT_PTR (struct acpi_namespace_node, &obj_desc));
 556                         /*
 557                          * The only case where we pass through (ignore) a NOT_FOUND
 558                          * error is for the cond_ref_of opcode.
 559                          */
 560                         if (status == AE_NOT_FOUND) {
 561                                 if (parent_op->common.aml_opcode == AML_COND_REF_OF_OP) {
 562                                         /*
 563                                          * For the Conditional Reference op, it's OK if
 564                                          * the name is not found;  We just need a way to
 565                                          * indicate this to the interpreter, set the
 566                                          * object to the root
 567                                          */
 568                                         obj_desc = ACPI_CAST_PTR (union acpi_operand_object, acpi_gbl_root_node);
 569                                         status = AE_OK;
 570                                 }
 571                                 else {
 572                                         /*
 573                                          * We just plain didn't find it -- which is a
 574                                          * very serious error at this point
 575                                          */
 576                                         status = AE_AML_NAME_NOT_FOUND;
 577                                 }
 578                         }
 579
 580                         if (ACPI_FAILURE (status)) {
 581                                 ACPI_REPORT_NSERROR (name_string, status);
 582                         }
 583                 }
 584
 585                 /* Free the namestring created above */
 586
 587                 ACPI_MEM_FREE (name_string);
 588
 589                 /* Check status from the lookup */
 590
 591                 if (ACPI_FAILURE (status)) {
 592                         return_ACPI_STATUS (status);
 593                 }
 594
 595                 /* Put the resulting object onto the current object stack */
 596
 597                 status = acpi_ds_obj_stack_push (obj_desc, walk_state);
 598                 if (ACPI_FAILURE (status)) {
 599                         return_ACPI_STATUS (status);
 600                 }
 601                 ACPI_DEBUGGER_EXEC (acpi_db_display_argument_object (obj_desc, walk_state));
 602         }
 603         else {
 604                 /* Check for null name case */
 605
 606                 if (arg->common.aml_opcode == AML_INT_NAMEPATH_OP) {
 607                         /*
 608                          * If the name is null, this means that this is an
 609                          * optional result parameter that was not specified
 610                          * in the original ASL.  Create a Zero Constant for a
 611                          * placeholder.  (Store to a constant is a Noop.)
 612                          */
 613                         opcode = AML_ZERO_OP;       /* Has no arguments! */
 614
 615                         ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "Null namepath: Arg=%p\n", arg));
 616                 }
 617                 else {
 618                         opcode = arg->common.aml_opcode;
 619                 }
 620
 621                 /* Get the object type of the argument */
 622
 623                 op_info = acpi_ps_get_opcode_info (opcode);
 624                 if (op_info->object_type == ACPI_TYPE_INVALID) {
 625                         return_ACPI_STATUS (AE_NOT_IMPLEMENTED);
 626                 }
 627
 628                 if (op_info->flags & AML_HAS_RETVAL) {
 629                         ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
 630                                 "Argument previously created, already stacked \n"));
 631
 632                         ACPI_DEBUGGER_EXEC (acpi_db_display_argument_object (
 633                                 walk_state->operands [walk_state->num_operands - 1], walk_state));
 634
 635                         /*
 636                          * Use value that was already previously returned
 637                          * by the evaluation of this argument
 638                          */
 639                         status = acpi_ds_result_pop_from_bottom (&obj_desc, walk_state);
 640                         if (ACPI_FAILURE (status)) {
 641                                 /*
 642                                  * Only error is underflow, and this indicates
 643                                  * a missing or null operand!
 644                                  */
 645                                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Missing or null operand, %s\n",
 646                                         acpi_format_exception (status)));
 647                                 return_ACPI_STATUS (status);
 648                         }
 649                 }
 650                 else {
 651                         /* Create an ACPI_INTERNAL_OBJECT for the argument */
 652
 653                         obj_desc = acpi_ut_create_internal_object (op_info->object_type);
 654                         if (!obj_desc) {
 655                                 return_ACPI_STATUS (AE_NO_MEMORY);
 656                         }
 657
 658                         /* Initialize the new object */
 659
 660                         status = acpi_ds_init_object_from_op (walk_state, arg,
 661                                          opcode, &obj_desc);
 662                         if (ACPI_FAILURE (status)) {
 663                                 acpi_ut_delete_object_desc (obj_desc);
 664                                 return_ACPI_STATUS (status);
 665                         }
 666                 }
 667
 668                 /* Put the operand object on the object stack */
 669
 670                 status = acpi_ds_obj_stack_push (obj_desc, walk_state);
 671                 if (ACPI_FAILURE (status)) {
 672                         return_ACPI_STATUS (status);
 673                 }
 674
 675                 ACPI_DEBUGGER_EXEC (acpi_db_display_argument_object (obj_desc, walk_state));
 676         }
 677
 678         return_ACPI_STATUS (AE_OK);
 679 }
 680
 681
 682 /*******************************************************************************
 683  *
 684  * FUNCTION:    acpi_ds_create_operands
 685  *
 686  * PARAMETERS:  walk_state          - Current state
 687  *              first_arg           - First argument of a parser argument tree
 688  *
 689  * RETURN:      Status
 690  *
 691  * DESCRIPTION: Convert an operator's arguments from a parse tree format to
 692  *              namespace objects and place those argument object on the object
 693  *              stack in preparation for evaluation by the interpreter.
 694  *
 695  ******************************************************************************/
 696
 697 acpi_status
 698 acpi_ds_create_operands (
 699         struct acpi_walk_state          *walk_state,
 700         union acpi_parse_object         *first_arg)
 701 {
 702         acpi_status                     status = AE_OK;
 703         union acpi_parse_object         *arg;
 704         u32                             arg_count = 0;
 705
 706
 707         ACPI_FUNCTION_TRACE_PTR ("ds_create_operands", first_arg);
 708
 709
 710         /* For all arguments in the list... */
 711
 712         arg = first_arg;
 713         while (arg) {
 714                 status = acpi_ds_create_operand (walk_state, arg, arg_count);
 715                 if (ACPI_FAILURE (status)) {
 716                         goto cleanup;
 717                 }
 718
 719                 ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "Arg #%d (%p) done, Arg1=%p\n",
 720                         arg_count, arg, first_arg));
 721
 722                 /* Move on to next argument, if any */
 723
 724                 arg = arg->common.next;
 725                 arg_count++;
 726         }
 727
 728         return_ACPI_STATUS (status);
 729
 730
 731 cleanup:
 732         /*
 733          * We must undo everything done above; meaning that we must
 734          * pop everything off of the operand stack and delete those
 735          * objects
 736          */
 737         (void) acpi_ds_obj_stack_pop_and_delete (arg_count, walk_state);
 738
 739         ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "While creating Arg %d - %s\n",
 740                 (arg_count + 1), acpi_format_exception (status)));
 741         return_ACPI_STATUS (status);
 742 }
 743
 744