drivers/acpi/dispatcher/dsmethod.c

   1 /******************************************************************************
   2  *
   3  * Module Name: dsmethod - Parser/Interpreter interface - control method parsing
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2004, 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
  52
  53 #define _COMPONENT          ACPI_DISPATCHER
  54          ACPI_MODULE_NAME    ("dsmethod")
  55
  56
  57 /*******************************************************************************
  58  *
  59  * FUNCTION:    acpi_ds_parse_method
  60  *
  61  * PARAMETERS:  obj_handle      - Node of the method
  62  *              Level           - Current nesting level
  63  *              Context         - Points to a method counter
  64  *              return_value    - Not used
  65  *
  66  * RETURN:      Status
  67  *
  68  * DESCRIPTION: Call the parser and parse the AML that is
  69  *              associated with the method.
  70  *
  71  * MUTEX:       Assumes parser is locked
  72  *
  73  ******************************************************************************/
  74
  75 acpi_status
  76 acpi_ds_parse_method (
  77         acpi_handle                     obj_handle)
  78 {
  79         acpi_status                     status;
  80         union acpi_operand_object       *obj_desc;
  81         union acpi_parse_object         *op;
  82         struct acpi_namespace_node      *node;
  83         acpi_owner_id                   owner_id;
  84         struct acpi_walk_state          *walk_state;
  85
  86
  87         ACPI_FUNCTION_TRACE_PTR ("ds_parse_method", obj_handle);
  88
  89
  90         /* Parameter Validation */
  91
  92         if (!obj_handle) {
  93                 return_ACPI_STATUS (AE_NULL_ENTRY);
  94         }
  95
  96         ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, "**** Parsing [%4.4s] **** named_obj=%p\n",
  97                 acpi_ut_get_node_name (obj_handle), obj_handle));
  98
  99         /* Extract the method object from the method Node */
 100
 101         node = (struct acpi_namespace_node *) obj_handle;
 102         obj_desc = acpi_ns_get_attached_object (node);
 103         if (!obj_desc) {
 104                 return_ACPI_STATUS (AE_NULL_OBJECT);
 105         }
 106
 107         /* Create a mutex for the method if there is a concurrency limit */
 108
 109         if ((obj_desc->method.concurrency != ACPI_INFINITE_CONCURRENCY) &&
 110                 (!obj_desc->method.semaphore)) {
 111                 status = acpi_os_create_semaphore (obj_desc->method.concurrency,
 112                                    obj_desc->method.concurrency,
 113                                    &obj_desc->method.semaphore);
 114                 if (ACPI_FAILURE (status)) {
 115                         return_ACPI_STATUS (status);
 116                 }
 117         }
 118
 119         /*
 120          * Allocate a new parser op to be the root of the parsed
 121          * method tree
 122          */
 123         op = acpi_ps_alloc_op (AML_METHOD_OP);
 124         if (!op) {
 125                 return_ACPI_STATUS (AE_NO_MEMORY);
 126         }
 127
 128         /* Init new op with the method name and pointer back to the Node */
 129
 130         acpi_ps_set_name (op, node->name.integer);
 131         op->common.node = node;
 132
 133         /*
 134          * Get a new owner_id for objects created by this method. Namespace
 135          * objects (such as Operation Regions) can be created during the
 136          * first pass parse.
 137          */
 138         owner_id = acpi_ut_allocate_owner_id (ACPI_OWNER_TYPE_METHOD);
 139         obj_desc->method.owning_id = owner_id;
 140
 141         /* Create and initialize a new walk state */
 142
 143         walk_state = acpi_ds_create_walk_state (owner_id, NULL, NULL, NULL);
 144         if (!walk_state) {
 145                 return_ACPI_STATUS (AE_NO_MEMORY);
 146         }
 147
 148         status = acpi_ds_init_aml_walk (walk_state, op, node, obj_desc->method.aml_start,
 149                           obj_desc->method.aml_length, NULL, NULL, 1);
 150         if (ACPI_FAILURE (status)) {
 151                 acpi_ds_delete_walk_state (walk_state);
 152                 return_ACPI_STATUS (status);
 153         }
 154
 155         /*
 156          * Parse the method, first pass
 157          *
 158          * The first pass load is where newly declared named objects are
 159          * added into the namespace.  Actual evaluation of
 160          * the named objects (what would be called a "second
 161          * pass") happens during the actual execution of the
 162          * method so that operands to the named objects can
 163          * take on dynamic run-time values.
 164          */
 165         status = acpi_ps_parse_aml (walk_state);
 166         if (ACPI_FAILURE (status)) {
 167                 return_ACPI_STATUS (status);
 168         }
 169
 170         ACPI_DEBUG_PRINT ((ACPI_DB_PARSE,
 171                 "**** [%4.4s] Parsed **** named_obj=%p Op=%p\n",
 172                 acpi_ut_get_node_name (obj_handle), obj_handle, op));
 173
 174         acpi_ps_delete_parse_tree (op);
 175         return_ACPI_STATUS (status);
 176 }
 177
 178
 179 /*******************************************************************************
 180  *
 181  * FUNCTION:    acpi_ds_begin_method_execution
 182  *
 183  * PARAMETERS:  method_node         - Node of the method
 184  *              obj_desc            - The method object
 185  *              calling_method_node - Caller of this method (if non-null)
 186  *
 187  * RETURN:      Status
 188  *
 189  * DESCRIPTION: Prepare a method for execution.  Parses the method if necessary,
 190  *              increments the thread count, and waits at the method semaphore
 191  *              for clearance to execute.
 192  *
 193  * MUTEX:       Locks/unlocks parser.
 194  *
 195  ******************************************************************************/
 196
 197 acpi_status
 198 acpi_ds_begin_method_execution (
 199         struct acpi_namespace_node      *method_node,
 200         union acpi_operand_object       *obj_desc,
 201         struct acpi_namespace_node      *calling_method_node)
 202 {
 203         acpi_status                     status = AE_OK;
 204
 205
 206         ACPI_FUNCTION_TRACE_PTR ("ds_begin_method_execution", method_node);
 207
 208
 209         if (!method_node) {
 210                 return_ACPI_STATUS (AE_NULL_ENTRY);
 211         }
 212
 213         /*
 214          * If there is a concurrency limit on this method, we need to
 215          * obtain a unit from the method semaphore.
 216          */
 217         if (obj_desc->method.semaphore) {
 218                 /*
 219                  * Allow recursive method calls, up to the reentrancy/concurrency
 220                  * limit imposed by the SERIALIZED rule and the sync_level method
 221                  * parameter.
 222                  *
 223                  * The point of this code is to avoid permanently blocking a
 224                  * thread that is making recursive method calls.
 225                  */
 226                 if (method_node == calling_method_node) {
 227                         if (obj_desc->method.thread_count >= obj_desc->method.concurrency) {
 228                                 return_ACPI_STATUS (AE_AML_METHOD_LIMIT);
 229                         }
 230                 }
 231
 232                 /*
 233                  * Get a unit from the method semaphore. This releases the
 234                  * interpreter if we block
 235                  */
 236                 status = acpi_ex_system_wait_semaphore (obj_desc->method.semaphore,
 237                                  ACPI_WAIT_FOREVER);
 238         }
 239
 240         /*
 241          * Increment the method parse tree thread count since it has been
 242          * reentered one more time (even if it is the same thread)
 243          */
 244         obj_desc->method.thread_count++;
 245         return_ACPI_STATUS (status);
 246 }
 247
 248
 249 /*******************************************************************************
 250  *
 251  * FUNCTION:    acpi_ds_call_control_method
 252  *
 253  * PARAMETERS:  walk_state          - Current state of the walk
 254  *              Op                  - Current Op to be walked
 255  *
 256  * RETURN:      Status
 257  *
 258  * DESCRIPTION: Transfer execution to a called control method
 259  *
 260  ******************************************************************************/
 261
 262 acpi_status
 263 acpi_ds_call_control_method (
 264         struct acpi_thread_state        *thread,
 265         struct acpi_walk_state          *this_walk_state,
 266         union acpi_parse_object         *op)
 267 {
 268         acpi_status                     status;
 269         struct acpi_namespace_node      *method_node;
 270         union acpi_operand_object       *obj_desc;
 271         struct acpi_walk_state          *next_walk_state;
 272         u32                             i;
 273
 274
 275         ACPI_FUNCTION_TRACE_PTR ("ds_call_control_method", this_walk_state);
 276
 277         ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "Execute method %p, currentstate=%p\n",
 278                 this_walk_state->prev_op, this_walk_state));
 279
 280         /*
 281          * Get the namespace entry for the control method we are about to call
 282          */
 283         method_node = this_walk_state->method_call_node;
 284         if (!method_node) {
 285                 return_ACPI_STATUS (AE_NULL_ENTRY);
 286         }
 287
 288         obj_desc = acpi_ns_get_attached_object (method_node);
 289         if (!obj_desc) {
 290                 return_ACPI_STATUS (AE_NULL_OBJECT);
 291         }
 292
 293         obj_desc->method.owning_id = acpi_ut_allocate_owner_id (ACPI_OWNER_TYPE_METHOD);
 294
 295         /* Init for new method, wait on concurrency semaphore */
 296
 297         status = acpi_ds_begin_method_execution (method_node, obj_desc,
 298                           this_walk_state->method_node);
 299         if (ACPI_FAILURE (status)) {
 300                 return_ACPI_STATUS (status);
 301         }
 302
 303         if (!(obj_desc->method.method_flags & AML_METHOD_INTERNAL_ONLY)) {
 304                 /* 1) Parse: Create a new walk state for the preempting walk */
 305
 306                 next_walk_state = acpi_ds_create_walk_state (obj_desc->method.owning_id,
 307                                   op, obj_desc, NULL);
 308                 if (!next_walk_state) {
 309                         return_ACPI_STATUS (AE_NO_MEMORY);
 310                 }
 311
 312
 313                 /* Create and init a Root Node */
 314
 315                 op = acpi_ps_create_scope_op ();
 316                 if (!op) {
 317                         status = AE_NO_MEMORY;
 318                         goto cleanup;
 319                 }
 320
 321                 status = acpi_ds_init_aml_walk (next_walk_state, op, method_node,
 322                                   obj_desc->method.aml_start, obj_desc->method.aml_length,
 323                                   NULL, NULL, 1);
 324                 if (ACPI_FAILURE (status)) {
 325                         acpi_ds_delete_walk_state (next_walk_state);
 326                         goto cleanup;
 327                 }
 328
 329                 /* Begin AML parse */
 330
 331                 status = acpi_ps_parse_aml (next_walk_state);
 332                 acpi_ps_delete_parse_tree (op);
 333         }
 334
 335         /* 2) Execute: Create a new state for the preempting walk */
 336
 337         next_walk_state = acpi_ds_create_walk_state (obj_desc->method.owning_id,
 338                           NULL, obj_desc, thread);
 339         if (!next_walk_state) {
 340                 status = AE_NO_MEMORY;
 341                 goto cleanup;
 342         }
 343         /*
 344          * The resolved arguments were put on the previous walk state's operand
 345          * stack.  Operands on the previous walk state stack always
 346          * start at index 0.
 347          * Null terminate the list of arguments
 348          */
 349         this_walk_state->operands [this_walk_state->num_operands] = NULL;
 350
 351         status = acpi_ds_init_aml_walk (next_walk_state, NULL, method_node,
 352                           obj_desc->method.aml_start, obj_desc->method.aml_length,
 353                           &this_walk_state->operands[0], NULL, 3);
 354         if (ACPI_FAILURE (status)) {
 355                 goto cleanup;
 356         }
 357
 358         /*
 359          * Delete the operands on the previous walkstate operand stack
 360          * (they were copied to new objects)
 361          */
 362         for (i = 0; i < obj_desc->method.param_count; i++) {
 363                 acpi_ut_remove_reference (this_walk_state->operands [i]);
 364                 this_walk_state->operands [i] = NULL;
 365         }
 366
 367         /* Clear the operand stack */
 368
 369         this_walk_state->num_operands = 0;
 370
 371         ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
 372                 "Starting nested execution, newstate=%p\n", next_walk_state));
 373
 374         if (obj_desc->method.method_flags & AML_METHOD_INTERNAL_ONLY) {
 375                 status = obj_desc->method.implementation (next_walk_state);
 376                 return_ACPI_STATUS (status);
 377         }
 378
 379         return_ACPI_STATUS (AE_OK);
 380
 381
 382         /* On error, we must delete the new walk state */
 383
 384 cleanup:
 385         if (next_walk_state->method_desc) {
 386                 /* Decrement the thread count on the method parse tree */
 387
 388            next_walk_state->method_desc->method.thread_count--;
 389         }
 390         (void) acpi_ds_terminate_control_method (next_walk_state);
 391         acpi_ds_delete_walk_state (next_walk_state);
 392         return_ACPI_STATUS (status);
 393 }
 394
 395
 396 /*******************************************************************************
 397  *
 398  * FUNCTION:    acpi_ds_restart_control_method
 399  *
 400  * PARAMETERS:  walk_state          - State of the method when it was preempted
 401  *              Op                  - Pointer to new current op
 402  *
 403  * RETURN:      Status
 404  *
 405  * DESCRIPTION: Restart a method that was preempted
 406  *
 407  ******************************************************************************/
 408
 409 acpi_status
 410 acpi_ds_restart_control_method (
 411         struct acpi_walk_state          *walk_state,
 412         union acpi_operand_object       *return_desc)
 413 {
 414         acpi_status                     status;
 415
 416
 417         ACPI_FUNCTION_TRACE_PTR ("ds_restart_control_method", walk_state);
 418
 419
 420         if (return_desc) {
 421                 if (walk_state->return_used) {
 422                         /*
 423                          * Get the return value (if any) from the previous method.
 424                          * NULL if no return value
 425                          */
 426                         status = acpi_ds_result_push (return_desc, walk_state);
 427                         if (ACPI_FAILURE (status)) {
 428                                 acpi_ut_remove_reference (return_desc);
 429                                 return_ACPI_STATUS (status);
 430                         }
 431                 }
 432                 else {
 433                         /*
 434                          * Delete the return value if it will not be used by the
 435                          * calling method
 436                          */
 437                         acpi_ut_remove_reference (return_desc);
 438                 }
 439         }
 440
 441         ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
 442                 "Method=%p Return=%p return_used?=%X res_stack=%p State=%p\n",
 443                 walk_state->method_call_op, return_desc, walk_state->return_used,
 444                 walk_state->results, walk_state));
 445
 446         return_ACPI_STATUS (AE_OK);
 447 }
 448
 449
 450 /*******************************************************************************
 451  *
 452  * FUNCTION:    acpi_ds_terminate_control_method
 453  *
 454  * PARAMETERS:  walk_state          - State of the method
 455  *
 456  * RETURN:      Status
 457  *
 458  * DESCRIPTION: Terminate a control method.  Delete everything that the method
 459  *              created, delete all locals and arguments, and delete the parse
 460  *              tree if requested.
 461  *
 462  ******************************************************************************/
 463
 464 acpi_status
 465 acpi_ds_terminate_control_method (
 466         struct acpi_walk_state          *walk_state)
 467 {
 468         union acpi_operand_object       *obj_desc;
 469         struct acpi_namespace_node      *method_node;
 470         acpi_status                     status;
 471
 472
 473         ACPI_FUNCTION_TRACE_PTR ("ds_terminate_control_method", walk_state);
 474
 475
 476         if (!walk_state) {
 477                 return (AE_BAD_PARAMETER);
 478         }
 479
 480         /* The current method object was saved in the walk state */
 481
 482         obj_desc = walk_state->method_desc;
 483         if (!obj_desc) {
 484                 return_ACPI_STATUS (AE_OK);
 485         }
 486
 487         /* Delete all arguments and locals */
 488
 489         acpi_ds_method_data_delete_all (walk_state);
 490
 491         /*
 492          * Lock the parser while we terminate this method.
 493          * If this is the last thread executing the method,
 494          * we have additional cleanup to perform
 495          */
 496         status = acpi_ut_acquire_mutex (ACPI_MTX_PARSER);
 497         if (ACPI_FAILURE (status)) {
 498                 return_ACPI_STATUS (status);
 499         }
 500
 501         /* Signal completion of the execution of this method if necessary */
 502
 503         if (walk_state->method_desc->method.semaphore) {
 504                 status = acpi_os_signal_semaphore (
 505                                   walk_state->method_desc->method.semaphore, 1);
 506                 if (ACPI_FAILURE (status)) {
 507                         ACPI_REPORT_ERROR (("Could not signal method semaphore\n"));
 508                         status = AE_OK;
 509
 510                         /* Ignore error and continue cleanup */
 511                 }
 512         }
 513
 514         if (walk_state->method_desc->method.thread_count) {
 515                 ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
 516                         "*** Not deleting method namespace, there are still %d threads\n",
 517                         walk_state->method_desc->method.thread_count));
 518         }
 519
 520         if (!walk_state->method_desc->method.thread_count) {
 521                 /*
 522                  * Support to dynamically change a method from not_serialized to
 523                  * Serialized if it appears that the method is written foolishly and
 524                  * does not support multiple thread execution.  The best example of this
 525                  * is if such a method creates namespace objects and blocks.  A second
 526                  * thread will fail with an AE_ALREADY_EXISTS exception
 527                  *
 528                  * This code is here because we must wait until the last thread exits
 529                  * before creating the synchronization semaphore.
 530                  */
 531                 if ((walk_state->method_desc->method.concurrency == 1) &&
 532                         (!walk_state->method_desc->method.semaphore)) {
 533                         status = acpi_os_create_semaphore (1,
 534                                          1,
 535                                          &walk_state->method_desc->method.semaphore);
 536                 }
 537
 538                 /*
 539                  * There are no more threads executing this method.  Perform
 540                  * additional cleanup.
 541                  *
 542                  * The method Node is stored in the walk state
 543                  */
 544                 method_node = walk_state->method_node;
 545
 546                 /*
 547                  * Delete any namespace entries created immediately underneath
 548                  * the method
 549                  */
 550                 status = acpi_ut_acquire_mutex (ACPI_MTX_NAMESPACE);
 551                 if (ACPI_FAILURE (status)) {
 552                         return_ACPI_STATUS (status);
 553                 }
 554
 555                 if (method_node->child) {
 556                         acpi_ns_delete_namespace_subtree (method_node);
 557                 }
 558
 559                 /*
 560                  * Delete any namespace entries created anywhere else within
 561                  * the namespace
 562                  */
 563                 acpi_ns_delete_namespace_by_owner (walk_state->method_desc->method.owning_id);
 564                 status = acpi_ut_release_mutex (ACPI_MTX_NAMESPACE);
 565                 if (ACPI_FAILURE (status)) {
 566                         return_ACPI_STATUS (status);
 567                 }
 568         }
 569
 570         status = acpi_ut_release_mutex (ACPI_MTX_PARSER);
 571         return_ACPI_STATUS (status);
 572 }
 573
 574