[ACPI] ACPICA 20050902
[linux-2.6] / drivers / acpi / utilities / utdelete.c
1 /*******************************************************************************
2  *
3  * Module Name: utdelete - object deletion and reference count 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 #include <acpi/acpi.h>
45 #include <acpi/acinterp.h>
46 #include <acpi/acnamesp.h>
47 #include <acpi/acevents.h>
48 #include <acpi/amlcode.h>
49
50 #define _COMPONENT          ACPI_UTILITIES
51 ACPI_MODULE_NAME("utdelete")
52
53 /* Local prototypes */
54 static void acpi_ut_delete_internal_obj(union acpi_operand_object *object);
55
56 static void
57 acpi_ut_update_ref_count(union acpi_operand_object *object, u32 action);
58
59 /*******************************************************************************
60  *
61  * FUNCTION:    acpi_ut_delete_internal_obj
62  *
63  * PARAMETERS:  Object         - Object to be deleted
64  *
65  * RETURN:      None
66  *
67  * DESCRIPTION: Low level object deletion, after reference counts have been
68  *              updated (All reference counts, including sub-objects!)
69  *
70  ******************************************************************************/
71
72 static void acpi_ut_delete_internal_obj(union acpi_operand_object *object)
73 {
74         void *obj_pointer = NULL;
75         union acpi_operand_object *handler_desc;
76         union acpi_operand_object *second_desc;
77         union acpi_operand_object *next_desc;
78
79         ACPI_FUNCTION_TRACE_PTR("ut_delete_internal_obj", object);
80
81         if (!object) {
82                 return_VOID;
83         }
84
85         /*
86          * Must delete or free any pointers within the object that are not
87          * actual ACPI objects (for example, a raw buffer pointer).
88          */
89         switch (ACPI_GET_OBJECT_TYPE(object)) {
90         case ACPI_TYPE_STRING:
91
92                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
93                                   "**** String %p, ptr %p\n", object,
94                                   object->string.pointer));
95
96                 /* Free the actual string buffer */
97
98                 if (!(object->common.flags & AOPOBJ_STATIC_POINTER)) {
99                         /* But only if it is NOT a pointer into an ACPI table */
100
101                         obj_pointer = object->string.pointer;
102                 }
103                 break;
104
105         case ACPI_TYPE_BUFFER:
106
107                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
108                                   "**** Buffer %p, ptr %p\n", object,
109                                   object->buffer.pointer));
110
111                 /* Free the actual buffer */
112
113                 if (!(object->common.flags & AOPOBJ_STATIC_POINTER)) {
114                         /* But only if it is NOT a pointer into an ACPI table */
115
116                         obj_pointer = object->buffer.pointer;
117                 }
118                 break;
119
120         case ACPI_TYPE_PACKAGE:
121
122                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
123                                   " **** Package of count %X\n",
124                                   object->package.count));
125
126                 /*
127                  * Elements of the package are not handled here, they are deleted
128                  * separately
129                  */
130
131                 /* Free the (variable length) element pointer array */
132
133                 obj_pointer = object->package.elements;
134                 break;
135
136         case ACPI_TYPE_DEVICE:
137
138                 if (object->device.gpe_block) {
139                         (void)acpi_ev_delete_gpe_block(object->device.
140                                                        gpe_block);
141                 }
142
143                 /* Walk the handler list for this device */
144
145                 handler_desc = object->device.handler;
146                 while (handler_desc) {
147                         next_desc = handler_desc->address_space.next;
148                         acpi_ut_remove_reference(handler_desc);
149                         handler_desc = next_desc;
150                 }
151                 break;
152
153         case ACPI_TYPE_MUTEX:
154
155                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
156                                   "***** Mutex %p, Semaphore %p\n",
157                                   object, object->mutex.semaphore));
158
159                 acpi_ex_unlink_mutex(object);
160                 (void)acpi_os_delete_semaphore(object->mutex.semaphore);
161                 break;
162
163         case ACPI_TYPE_EVENT:
164
165                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
166                                   "***** Event %p, Semaphore %p\n",
167                                   object, object->event.semaphore));
168
169                 (void)acpi_os_delete_semaphore(object->event.semaphore);
170                 object->event.semaphore = NULL;
171                 break;
172
173         case ACPI_TYPE_METHOD:
174
175                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
176                                   "***** Method %p\n", object));
177
178                 /* Delete the method semaphore if it exists */
179
180                 if (object->method.semaphore) {
181                         (void)acpi_os_delete_semaphore(object->method.
182                                                        semaphore);
183                         object->method.semaphore = NULL;
184                 }
185                 break;
186
187         case ACPI_TYPE_REGION:
188
189                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
190                                   "***** Region %p\n", object));
191
192                 second_desc = acpi_ns_get_secondary_object(object);
193                 if (second_desc) {
194                         /*
195                          * Free the region_context if and only if the handler is one of the
196                          * default handlers -- and therefore, we created the context object
197                          * locally, it was not created by an external caller.
198                          */
199                         handler_desc = object->region.handler;
200                         if (handler_desc) {
201                                 if (handler_desc->address_space.
202                                     hflags &
203                                     ACPI_ADDR_HANDLER_DEFAULT_INSTALLED) {
204                                         obj_pointer =
205                                             second_desc->extra.region_context;
206                                 }
207
208                                 acpi_ut_remove_reference(handler_desc);
209                         }
210
211                         /* Now we can free the Extra object */
212
213                         acpi_ut_delete_object_desc(second_desc);
214                 }
215                 break;
216
217         case ACPI_TYPE_BUFFER_FIELD:
218
219                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
220                                   "***** Buffer Field %p\n", object));
221
222                 second_desc = acpi_ns_get_secondary_object(object);
223                 if (second_desc) {
224                         acpi_ut_delete_object_desc(second_desc);
225                 }
226                 break;
227
228         default:
229                 break;
230         }
231
232         /* Free any allocated memory (pointer within the object) found above */
233
234         if (obj_pointer) {
235                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
236                                   "Deleting Object Subptr %p\n", obj_pointer));
237                 ACPI_MEM_FREE(obj_pointer);
238         }
239
240         /* Now the object can be safely deleted */
241
242         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS, "Deleting Object %p [%s]\n",
243                           object, acpi_ut_get_object_type_name(object)));
244
245         acpi_ut_delete_object_desc(object);
246         return_VOID;
247 }
248
249 /*******************************************************************************
250  *
251  * FUNCTION:    acpi_ut_delete_internal_object_list
252  *
253  * PARAMETERS:  obj_list        - Pointer to the list to be deleted
254  *
255  * RETURN:      None
256  *
257  * DESCRIPTION: This function deletes an internal object list, including both
258  *              simple objects and package objects
259  *
260  ******************************************************************************/
261
262 void acpi_ut_delete_internal_object_list(union acpi_operand_object **obj_list)
263 {
264         union acpi_operand_object **internal_obj;
265
266         ACPI_FUNCTION_TRACE("ut_delete_internal_object_list");
267
268         /* Walk the null-terminated internal list */
269
270         for (internal_obj = obj_list; *internal_obj; internal_obj++) {
271                 acpi_ut_remove_reference(*internal_obj);
272         }
273
274         /* Free the combined parameter pointer list and object array */
275
276         ACPI_MEM_FREE(obj_list);
277         return_VOID;
278 }
279
280 /*******************************************************************************
281  *
282  * FUNCTION:    acpi_ut_update_ref_count
283  *
284  * PARAMETERS:  Object          - Object whose ref count is to be updated
285  *              Action          - What to do
286  *
287  * RETURN:      New ref count
288  *
289  * DESCRIPTION: Modify the ref count and return it.
290  *
291  ******************************************************************************/
292
293 static void
294 acpi_ut_update_ref_count(union acpi_operand_object *object, u32 action)
295 {
296         u16 count;
297         u16 new_count;
298
299         ACPI_FUNCTION_NAME("ut_update_ref_count");
300
301         if (!object) {
302                 return;
303         }
304
305         count = object->common.reference_count;
306         new_count = count;
307
308         /*
309          * Perform the reference count action
310          * (increment, decrement, or force delete)
311          */
312         switch (action) {
313
314         case REF_INCREMENT:
315
316                 new_count++;
317                 object->common.reference_count = new_count;
318
319                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
320                                   "Obj %p Refs=%X, [Incremented]\n",
321                                   object, new_count));
322                 break;
323
324         case REF_DECREMENT:
325
326                 if (count < 1) {
327                         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
328                                           "Obj %p Refs=%X, can't decrement! (Set to 0)\n",
329                                           object, new_count));
330
331                         new_count = 0;
332                 } else {
333                         new_count--;
334
335                         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
336                                           "Obj %p Refs=%X, [Decremented]\n",
337                                           object, new_count));
338                 }
339
340                 if (ACPI_GET_OBJECT_TYPE(object) == ACPI_TYPE_METHOD) {
341                         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
342                                           "Method Obj %p Refs=%X, [Decremented]\n",
343                                           object, new_count));
344                 }
345
346                 object->common.reference_count = new_count;
347                 if (new_count == 0) {
348                         acpi_ut_delete_internal_obj(object);
349                 }
350
351                 break;
352
353         case REF_FORCE_DELETE:
354
355                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
356                                   "Obj %p Refs=%X, Force delete! (Set to 0)\n",
357                                   object, count));
358
359                 new_count = 0;
360                 object->common.reference_count = new_count;
361                 acpi_ut_delete_internal_obj(object);
362                 break;
363
364         default:
365
366                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Unknown action (%X)\n",
367                                   action));
368                 break;
369         }
370
371         /*
372          * Sanity check the reference count, for debug purposes only.
373          * (A deleted object will have a huge reference count)
374          */
375         if (count > ACPI_MAX_REFERENCE_COUNT) {
376
377                 ACPI_DEBUG_PRINT((ACPI_DB_WARN,
378                                   "**** Warning **** Large Reference Count (%X) in object %p\n\n",
379                                   count, object));
380         }
381
382         return;
383 }
384
385 /*******************************************************************************
386  *
387  * FUNCTION:    acpi_ut_update_object_reference
388  *
389  * PARAMETERS:  Object              - Increment ref count for this object
390  *                                    and all sub-objects
391  *              Action              - Either REF_INCREMENT or REF_DECREMENT or
392  *                                    REF_FORCE_DELETE
393  *
394  * RETURN:      Status
395  *
396  * DESCRIPTION: Increment the object reference count
397  *
398  * Object references are incremented when:
399  * 1) An object is attached to a Node (namespace object)
400  * 2) An object is copied (all subobjects must be incremented)
401  *
402  * Object references are decremented when:
403  * 1) An object is detached from an Node
404  *
405  ******************************************************************************/
406
407 acpi_status
408 acpi_ut_update_object_reference(union acpi_operand_object * object, u16 action)
409 {
410         acpi_status status = AE_OK;
411         union acpi_generic_state *state_list = NULL;
412         union acpi_operand_object *next_object = NULL;
413         union acpi_generic_state *state;
414         acpi_native_uint i;
415
416         ACPI_FUNCTION_TRACE_PTR("ut_update_object_reference", object);
417
418         while (object) {
419                 /* Make sure that this isn't a namespace handle */
420
421                 if (ACPI_GET_DESCRIPTOR_TYPE(object) == ACPI_DESC_TYPE_NAMED) {
422                         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
423                                           "Object %p is NS handle\n", object));
424                         return_ACPI_STATUS(AE_OK);
425                 }
426
427                 /*
428                  * All sub-objects must have their reference count incremented also.
429                  * Different object types have different subobjects.
430                  */
431                 switch (ACPI_GET_OBJECT_TYPE(object)) {
432                 case ACPI_TYPE_DEVICE:
433
434                         acpi_ut_update_ref_count(object->device.system_notify,
435                                                  action);
436                         acpi_ut_update_ref_count(object->device.device_notify,
437                                                  action);
438                         break;
439
440                 case ACPI_TYPE_PACKAGE:
441                         /*
442                          * We must update all the sub-objects of the package,
443                          * each of whom may have their own sub-objects.
444                          */
445                         for (i = 0; i < object->package.count; i++) {
446                                 /*
447                                  * Push each element onto the stack for later processing.
448                                  * Note: There can be null elements within the package,
449                                  * these are simply ignored
450                                  */
451                                 status =
452                                     acpi_ut_create_update_state_and_push
453                                     (object->package.elements[i], action,
454                                      &state_list);
455                                 if (ACPI_FAILURE(status)) {
456                                         goto error_exit;
457                                 }
458                         }
459                         break;
460
461                 case ACPI_TYPE_BUFFER_FIELD:
462
463                         next_object = object->buffer_field.buffer_obj;
464                         break;
465
466                 case ACPI_TYPE_LOCAL_REGION_FIELD:
467
468                         next_object = object->field.region_obj;
469                         break;
470
471                 case ACPI_TYPE_LOCAL_BANK_FIELD:
472
473                         next_object = object->bank_field.bank_obj;
474                         status =
475                             acpi_ut_create_update_state_and_push(object->
476                                                                  bank_field.
477                                                                  region_obj,
478                                                                  action,
479                                                                  &state_list);
480                         if (ACPI_FAILURE(status)) {
481                                 goto error_exit;
482                         }
483                         break;
484
485                 case ACPI_TYPE_LOCAL_INDEX_FIELD:
486
487                         next_object = object->index_field.index_obj;
488                         status =
489                             acpi_ut_create_update_state_and_push(object->
490                                                                  index_field.
491                                                                  data_obj,
492                                                                  action,
493                                                                  &state_list);
494                         if (ACPI_FAILURE(status)) {
495                                 goto error_exit;
496                         }
497                         break;
498
499                 case ACPI_TYPE_LOCAL_REFERENCE:
500                         /*
501                          * The target of an Index (a package, string, or buffer) must track
502                          * changes to the ref count of the index.
503                          */
504                         if (object->reference.opcode == AML_INDEX_OP) {
505                                 next_object = object->reference.object;
506                         }
507                         break;
508
509                 case ACPI_TYPE_REGION:
510                 default:
511                         break;  /* No subobjects */
512                 }
513
514                 /*
515                  * Now we can update the count in the main object.  This can only
516                  * happen after we update the sub-objects in case this causes the
517                  * main object to be deleted.
518                  */
519                 acpi_ut_update_ref_count(object, action);
520                 object = NULL;
521
522                 /* Move on to the next object to be updated */
523
524                 if (next_object) {
525                         object = next_object;
526                         next_object = NULL;
527                 } else if (state_list) {
528                         state = acpi_ut_pop_generic_state(&state_list);
529                         object = state->update.object;
530                         acpi_ut_delete_generic_state(state);
531                 }
532         }
533
534         return_ACPI_STATUS(AE_OK);
535
536       error_exit:
537
538         ACPI_REPORT_ERROR(("Could not update object reference count, %s\n",
539                            acpi_format_exception(status)));
540
541         return_ACPI_STATUS(status);
542 }
543
544 /*******************************************************************************
545  *
546  * FUNCTION:    acpi_ut_add_reference
547  *
548  * PARAMETERS:  Object          - Object whose reference count is to be
549  *                                incremented
550  *
551  * RETURN:      None
552  *
553  * DESCRIPTION: Add one reference to an ACPI object
554  *
555  ******************************************************************************/
556
557 void acpi_ut_add_reference(union acpi_operand_object *object)
558 {
559
560         ACPI_FUNCTION_TRACE_PTR("ut_add_reference", object);
561
562         /* Ensure that we have a valid object */
563
564         if (!acpi_ut_valid_internal_object(object)) {
565                 return_VOID;
566         }
567
568         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
569                           "Obj %p Current Refs=%X [To Be Incremented]\n",
570                           object, object->common.reference_count));
571
572         /* Increment the reference count */
573
574         (void)acpi_ut_update_object_reference(object, REF_INCREMENT);
575         return_VOID;
576 }
577
578 /*******************************************************************************
579  *
580  * FUNCTION:    acpi_ut_remove_reference
581  *
582  * PARAMETERS:  Object         - Object whose ref count will be decremented
583  *
584  * RETURN:      None
585  *
586  * DESCRIPTION: Decrement the reference count of an ACPI internal object
587  *
588  ******************************************************************************/
589
590 void acpi_ut_remove_reference(union acpi_operand_object *object)
591 {
592
593         ACPI_FUNCTION_TRACE_PTR("ut_remove_reference", object);
594
595         /*
596          * Allow a NULL pointer to be passed in, just ignore it.  This saves
597          * each caller from having to check.  Also, ignore NS nodes.
598          *
599          */
600         if (!object ||
601             (ACPI_GET_DESCRIPTOR_TYPE(object) == ACPI_DESC_TYPE_NAMED)) {
602                 return_VOID;
603         }
604
605         /* Ensure that we have a valid object */
606
607         if (!acpi_ut_valid_internal_object(object)) {
608                 return_VOID;
609         }
610
611         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
612                           "Obj %p Current Refs=%X [To Be Decremented]\n",
613                           object, object->common.reference_count));
614
615         /*
616          * Decrement the reference count, and only actually delete the object
617          * if the reference count becomes 0.  (Must also decrement the ref count
618          * of all subobjects!)
619          */
620         (void)acpi_ut_update_object_reference(object, REF_DECREMENT);
621         return_VOID;
622 }