drivers/acpi/namespace/nseval.c

   1 /*******************************************************************************
   2  *
   3  * Module Name: nseval - Object evaluation interfaces -- includes control
   4  *                       method lookup and execution.
   5  *
   6  ******************************************************************************/
   7
   8 /*
   9  * Copyright (C) 2000 - 2005, R. Byron Moore
  10  * All rights reserved.
  11  *
  12  * Redistribution and use in source and binary forms, with or without
  13  * modification, are permitted provided that the following conditions
  14  * are met:
  15  * 1. Redistributions of source code must retain the above copyright
  16  *    notice, this list of conditions, and the following disclaimer,
  17  *    without modification.
  18  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  19  *    substantially similar to the "NO WARRANTY" disclaimer below
  20  *    ("Disclaimer") and any redistribution must be conditioned upon
  21  *    including a substantially similar Disclaimer requirement for further
  22  *    binary redistribution.
  23  * 3. Neither the names of the above-listed copyright holders nor the names
  24  *    of any contributors may be used to endorse or promote products derived
  25  *    from this software without specific prior written permission.
  26  *
  27  * Alternatively, this software may be distributed under the terms of the
  28  * GNU General Public License ("GPL") version 2 as published by the Free
  29  * Software Foundation.
  30  *
  31  * NO WARRANTY
  32  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  33  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  34  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  35  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  36  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  37  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  38  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  39  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  40  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  41  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  42  * POSSIBILITY OF SUCH DAMAGES.
  43  */
  44
  45
  46 #include <acpi/acpi.h>
  47 #include <acpi/acparser.h>
  48 #include <acpi/acinterp.h>
  49 #include <acpi/acnamesp.h>
  50
  51
  52 #define _COMPONENT          ACPI_NAMESPACE
  53          ACPI_MODULE_NAME    ("nseval")
  54
  55 /* Local prototypes */
  56
  57 static acpi_status
  58 acpi_ns_execute_control_method (
  59         struct acpi_parameter_info      *info);
  60
  61 static acpi_status
  62 acpi_ns_get_object_value (
  63         struct acpi_parameter_info      *info);
  64
  65
  66 /*******************************************************************************
  67  *
  68  * FUNCTION:    acpi_ns_evaluate_relative
  69  *
  70  * PARAMETERS:  Pathname        - Name of method to execute, If NULL, the
  71  *                                handle is the object to execute
  72  *              Info            - Method info block, contains:
  73  *                  return_object   - Where to put method's return value (if
  74  *                                    any).  If NULL, no value is returned.
  75  *                  Params          - List of parameters to pass to the method,
  76  *                                    terminated by NULL.  Params itself may be
  77  *                                    NULL if no parameters are being passed.
  78  *
  79  * RETURN:      Status
  80  *
  81  * DESCRIPTION: Evaluate the object or find and execute the requested method
  82  *
  83  * MUTEX:       Locks Namespace
  84  *
  85  ******************************************************************************/
  86
  87 acpi_status
  88 acpi_ns_evaluate_relative (
  89         char                            *pathname,
  90         struct acpi_parameter_info      *info)
  91 {
  92         acpi_status                     status;
  93         struct acpi_namespace_node      *node = NULL;
  94         union acpi_generic_state        *scope_info;
  95         char                            *internal_path = NULL;
  96
  97
  98         ACPI_FUNCTION_TRACE ("ns_evaluate_relative");
  99
 100
 101         /*
 102          * Must have a valid object handle
 103          */
 104         if (!info || !info->node) {
 105                 return_ACPI_STATUS (AE_BAD_PARAMETER);
 106         }
 107
 108         /* Build an internal name string for the method */
 109
 110         status = acpi_ns_internalize_name (pathname, &internal_path);
 111         if (ACPI_FAILURE (status)) {
 112                 return_ACPI_STATUS (status);
 113         }
 114
 115         scope_info = acpi_ut_create_generic_state ();
 116         if (!scope_info) {
 117                 goto cleanup1;
 118         }
 119
 120         /* Get the prefix handle and Node */
 121
 122         status = acpi_ut_acquire_mutex (ACPI_MTX_NAMESPACE);
 123         if (ACPI_FAILURE (status)) {
 124                 goto cleanup;
 125         }
 126
 127         info->node = acpi_ns_map_handle_to_node (info->node);
 128         if (!info->node) {
 129                 (void) acpi_ut_release_mutex (ACPI_MTX_NAMESPACE);
 130                 status = AE_BAD_PARAMETER;
 131                 goto cleanup;
 132         }
 133
 134         /* Lookup the name in the namespace */
 135
 136         scope_info->scope.node = info->node;
 137         status = acpi_ns_lookup (scope_info, internal_path, ACPI_TYPE_ANY,
 138                          ACPI_IMODE_EXECUTE, ACPI_NS_NO_UPSEARCH, NULL,
 139                          &node);
 140
 141         (void) acpi_ut_release_mutex (ACPI_MTX_NAMESPACE);
 142
 143         if (ACPI_FAILURE (status)) {
 144                 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, "Object [%s] not found [%s]\n",
 145                         pathname, acpi_format_exception (status)));
 146                 goto cleanup;
 147         }
 148
 149         /*
 150          * Now that we have a handle to the object, we can attempt to evaluate it.
 151          */
 152         ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, "%s [%p] Value %p\n",
 153                 pathname, node, acpi_ns_get_attached_object (node)));
 154
 155         info->node = node;
 156         status = acpi_ns_evaluate_by_handle (info);
 157
 158         ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, "*** Completed eval of object %s ***\n",
 159                 pathname));
 160
 161 cleanup:
 162         acpi_ut_delete_generic_state (scope_info);
 163
 164 cleanup1:
 165         ACPI_MEM_FREE (internal_path);
 166         return_ACPI_STATUS (status);
 167 }
 168
 169
 170 /*******************************************************************************
 171  *
 172  * FUNCTION:    acpi_ns_evaluate_by_name
 173  *
 174  * PARAMETERS:  Pathname        - Fully qualified pathname to the object
 175  *              Info                - Method info block, contains:
 176  *                  return_object   - Where to put method's return value (if
 177  *                                    any).  If NULL, no value is returned.
 178  *                  Params          - List of parameters to pass to the method,
 179  *                                    terminated by NULL.  Params itself may be
 180  *                                    NULL if no parameters are being passed.
 181  *
 182  * RETURN:      Status
 183  *
 184  * DESCRIPTION: Evaluate the object or rind and execute the requested method
 185  *              passing the given parameters
 186  *
 187  * MUTEX:       Locks Namespace
 188  *
 189  ******************************************************************************/
 190
 191 acpi_status
 192 acpi_ns_evaluate_by_name (
 193         char                            *pathname,
 194         struct acpi_parameter_info      *info)
 195 {
 196         acpi_status                     status;
 197         char                            *internal_path = NULL;
 198
 199
 200         ACPI_FUNCTION_TRACE ("ns_evaluate_by_name");
 201
 202
 203         /* Build an internal name string for the method */
 204
 205         status = acpi_ns_internalize_name (pathname, &internal_path);
 206         if (ACPI_FAILURE (status)) {
 207                 return_ACPI_STATUS (status);
 208         }
 209
 210         status = acpi_ut_acquire_mutex (ACPI_MTX_NAMESPACE);
 211         if (ACPI_FAILURE (status)) {
 212                 goto cleanup;
 213         }
 214
 215         /* Lookup the name in the namespace */
 216
 217         status = acpi_ns_lookup (NULL, internal_path, ACPI_TYPE_ANY,
 218                          ACPI_IMODE_EXECUTE, ACPI_NS_NO_UPSEARCH, NULL,
 219                          &info->node);
 220
 221         (void) acpi_ut_release_mutex (ACPI_MTX_NAMESPACE);
 222
 223         if (ACPI_FAILURE (status)) {
 224                 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
 225                         "Object at [%s] was not found, status=%.4X\n",
 226                         pathname, status));
 227                 goto cleanup;
 228         }
 229
 230         /*
 231          * Now that we have a handle to the object, we can attempt to evaluate it.
 232          */
 233         ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, "%s [%p] Value %p\n",
 234                 pathname, info->node, acpi_ns_get_attached_object (info->node)));
 235
 236         status = acpi_ns_evaluate_by_handle (info);
 237
 238         ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, "*** Completed eval of object %s ***\n",
 239                 pathname));
 240
 241
 242 cleanup:
 243
 244         /* Cleanup */
 245
 246         if (internal_path) {
 247                 ACPI_MEM_FREE (internal_path);
 248         }
 249
 250         return_ACPI_STATUS (status);
 251 }
 252
 253
 254 /*******************************************************************************
 255  *
 256  * FUNCTION:    acpi_ns_evaluate_by_handle
 257  *
 258  * PARAMETERS:  Info            - Method info block, contains:
 259  *                  Node            - Method/Object Node to execute
 260  *                  Parameters      - List of parameters to pass to the method,
 261  *                                    terminated by NULL. Params itself may be
 262  *                                    NULL if no parameters are being passed.
 263  *                  return_object   - Where to put method's return value (if
 264  *                                    any). If NULL, no value is returned.
 265  *                  parameter_type  - Type of Parameter list
 266  *                  return_object   - Where to put method's return value (if
 267  *                                    any). If NULL, no value is returned.
 268  *
 269  * RETURN:      Status
 270  *
 271  * DESCRIPTION: Evaluate object or execute the requested method passing the
 272  *              given parameters
 273  *
 274  * MUTEX:       Locks Namespace
 275  *
 276  ******************************************************************************/
 277
 278 acpi_status
 279 acpi_ns_evaluate_by_handle (
 280         struct acpi_parameter_info      *info)
 281 {
 282         acpi_status                     status;
 283
 284
 285         ACPI_FUNCTION_TRACE ("ns_evaluate_by_handle");
 286
 287
 288         /* Check if namespace has been initialized */
 289
 290         if (!acpi_gbl_root_node) {
 291                 return_ACPI_STATUS (AE_NO_NAMESPACE);
 292         }
 293
 294         /* Parameter Validation */
 295
 296         if (!info) {
 297                 return_ACPI_STATUS (AE_BAD_PARAMETER);
 298         }
 299
 300         /* Initialize the return value to an invalid object */
 301
 302         info->return_object = NULL;
 303
 304         /* Get the prefix handle and Node */
 305
 306         status = acpi_ut_acquire_mutex (ACPI_MTX_NAMESPACE);
 307         if (ACPI_FAILURE (status)) {
 308                 return_ACPI_STATUS (status);
 309         }
 310
 311         info->node = acpi_ns_map_handle_to_node (info->node);
 312         if (!info->node) {
 313                 (void) acpi_ut_release_mutex (ACPI_MTX_NAMESPACE);
 314                 return_ACPI_STATUS (AE_BAD_PARAMETER);
 315         }
 316
 317         /*
 318          * For a method alias, we must grab the actual method node so that proper
 319          * scoping context will be established before execution.
 320          */
 321         if (acpi_ns_get_type (info->node) == ACPI_TYPE_LOCAL_METHOD_ALIAS) {
 322                 info->node = ACPI_CAST_PTR (struct acpi_namespace_node, info->node->object);
 323         }
 324
 325         /*
 326          * Two major cases here:
 327          * 1) The object is an actual control method -- execute it.
 328          * 2) The object is not a method -- just return it's current value
 329          *
 330          * In both cases, the namespace is unlocked by the acpi_ns* procedure
 331          */
 332         if (acpi_ns_get_type (info->node) == ACPI_TYPE_METHOD) {
 333                 /*
 334                  * Case 1) We have an actual control method to execute
 335                  */
 336                 status = acpi_ns_execute_control_method (info);
 337         }
 338         else {
 339                 /*
 340                  * Case 2) Object is NOT a method, just return its current value
 341                  */
 342                 status = acpi_ns_get_object_value (info);
 343         }
 344
 345         /*
 346          * Check if there is a return value on the stack that must be dealt with
 347          */
 348         if (status == AE_CTRL_RETURN_VALUE) {
 349                 /* Map AE_CTRL_RETURN_VALUE to AE_OK, we are done with it */
 350
 351                 status = AE_OK;
 352         }
 353
 354         /*
 355          * Namespace was unlocked by the handling acpi_ns* function, so we
 356          * just return
 357          */
 358         return_ACPI_STATUS (status);
 359 }
 360
 361
 362 /*******************************************************************************
 363  *
 364  * FUNCTION:    acpi_ns_execute_control_method
 365  *
 366  * PARAMETERS:  Info            - Method info block, contains:
 367  *                  Node            - Method Node to execute
 368  *                  obj_desc        - Method object
 369  *                  Parameters      - List of parameters to pass to the method,
 370  *                                    terminated by NULL. Params itself may be
 371  *                                    NULL if no parameters are being passed.
 372  *                  return_object   - Where to put method's return value (if
 373  *                                    any). If NULL, no value is returned.
 374  *                  parameter_type  - Type of Parameter list
 375  *                  return_object   - Where to put method's return value (if
 376  *                                    any). If NULL, no value is returned.
 377  *
 378  * RETURN:      Status
 379  *
 380  * DESCRIPTION: Execute the requested method passing the given parameters
 381  *
 382  * MUTEX:       Assumes namespace is locked
 383  *
 384  ******************************************************************************/
 385
 386 static acpi_status
 387 acpi_ns_execute_control_method (
 388         struct acpi_parameter_info      *info)
 389 {
 390         acpi_status                     status;
 391
 392
 393         ACPI_FUNCTION_TRACE ("ns_execute_control_method");
 394
 395
 396         /* Verify that there is a method associated with this object */
 397
 398         info->obj_desc = acpi_ns_get_attached_object (info->node);
 399         if (!info->obj_desc) {
 400                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "No attached method object\n"));
 401
 402                 (void) acpi_ut_release_mutex (ACPI_MTX_NAMESPACE);
 403                 return_ACPI_STATUS (AE_NULL_OBJECT);
 404         }
 405
 406         ACPI_DUMP_PATHNAME (info->node, "Execute Method:",
 407                 ACPI_LV_INFO, _COMPONENT);
 408
 409         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Method at AML address %p Length %X\n",
 410                 info->obj_desc->method.aml_start + 1, info->obj_desc->method.aml_length - 1));
 411
 412         /*
 413          * Unlock the namespace before execution.  This allows namespace access
 414          * via the external Acpi* interfaces while a method is being executed.
 415          * However, any namespace deletion must acquire both the namespace and
 416          * interpreter locks to ensure that no thread is using the portion of the
 417          * namespace that is being deleted.
 418          */
 419         status = acpi_ut_release_mutex (ACPI_MTX_NAMESPACE);
 420         if (ACPI_FAILURE (status)) {
 421                 return_ACPI_STATUS (status);
 422         }
 423
 424         /*
 425          * Execute the method via the interpreter.  The interpreter is locked
 426          * here before calling into the AML parser
 427          */
 428         status = acpi_ex_enter_interpreter ();
 429         if (ACPI_FAILURE (status)) {
 430                 return_ACPI_STATUS (status);
 431         }
 432
 433         status = acpi_ps_execute_method (info);
 434         acpi_ex_exit_interpreter ();
 435
 436         return_ACPI_STATUS (status);
 437 }
 438
 439
 440 /*******************************************************************************
 441  *
 442  * FUNCTION:    acpi_ns_get_object_value
 443  *
 444  * PARAMETERS:  Info            - Method info block, contains:
 445  *                  Node            - Object's NS node
 446  *                  return_object   - Where to put object value (if
 447  *                                    any). If NULL, no value is returned.
 448  *
 449  * RETURN:      Status
 450  *
 451  * DESCRIPTION: Return the current value of the object
 452  *
 453  * MUTEX:       Assumes namespace is locked, leaves namespace unlocked
 454  *
 455  ******************************************************************************/
 456
 457 static acpi_status
 458 acpi_ns_get_object_value (
 459         struct acpi_parameter_info      *info)
 460 {
 461         acpi_status                     status = AE_OK;
 462         struct acpi_namespace_node      *resolved_node = info->node;
 463
 464
 465         ACPI_FUNCTION_TRACE ("ns_get_object_value");
 466
 467
 468         /*
 469          * Objects require additional resolution steps (e.g., the Node may be a
 470          * field that must be read, etc.) -- we can't just grab the object out of
 471          * the node.
 472          */
 473
 474         /*
 475          * Use resolve_node_to_value() to get the associated value. This call always
 476          * deletes obj_desc (allocated above).
 477          *
 478          * NOTE: we can get away with passing in NULL for a walk state because
 479          * obj_desc is guaranteed to not be a reference to either a method local or
 480          * a method argument (because this interface can only be called from the
 481          * acpi_evaluate external interface, never called from a running method.)
 482          *
 483          * Even though we do not directly invoke the interpreter for this, we must
 484          * enter it because we could access an opregion. The opregion access code
 485          * assumes that the interpreter is locked.
 486          *
 487          * We must release the namespace lock before entering the intepreter.
 488          */
 489         status = acpi_ut_release_mutex (ACPI_MTX_NAMESPACE);
 490         if (ACPI_FAILURE (status)) {
 491                 return_ACPI_STATUS (status);
 492         }
 493
 494         status = acpi_ex_enter_interpreter ();
 495         if (ACPI_SUCCESS (status)) {
 496                 status = acpi_ex_resolve_node_to_value (&resolved_node, NULL);
 497                 /*
 498                  * If acpi_ex_resolve_node_to_value() succeeded, the return value was placed
 499                  * in resolved_node.
 500                  */
 501                 acpi_ex_exit_interpreter ();
 502
 503                 if (ACPI_SUCCESS (status)) {
 504                         status = AE_CTRL_RETURN_VALUE;
 505                         info->return_object = ACPI_CAST_PTR
 506                                          (union acpi_operand_object, resolved_node);
 507                         ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, "Returning object %p [%s]\n",
 508                                 info->return_object,
 509                                 acpi_ut_get_object_type_name (info->return_object)));
 510                 }
 511         }
 512
 513         /* Namespace is unlocked */
 514
 515         return_ACPI_STATUS (status);
 516 }
 517