Merge branch 'linus' into x86/paravirt-spinlocks
[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 - 2008, Intel Corp.
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
100                         /* But only if it is NOT a pointer into an ACPI table */
101
102                         obj_pointer = object->string.pointer;
103                 }
104                 break;
105
106         case ACPI_TYPE_BUFFER:
107
108                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
109                                   "**** Buffer %p, ptr %p\n", object,
110                                   object->buffer.pointer));
111
112                 /* Free the actual buffer */
113
114                 if (!(object->common.flags & AOPOBJ_STATIC_POINTER)) {
115
116                         /* But only if it is NOT a pointer into an ACPI table */
117
118                         obj_pointer = object->buffer.pointer;
119                 }
120                 break;
121
122         case ACPI_TYPE_PACKAGE:
123
124                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
125                                   " **** Package of count %X\n",
126                                   object->package.count));
127
128                 /*
129                  * Elements of the package are not handled here, they are deleted
130                  * separately
131                  */
132
133                 /* Free the (variable length) element pointer array */
134
135                 obj_pointer = object->package.elements;
136                 break;
137
138         case ACPI_TYPE_DEVICE:
139
140                 if (object->device.gpe_block) {
141                         (void)acpi_ev_delete_gpe_block(object->device.
142                                                        gpe_block);
143                 }
144
145                 /* Walk the handler list for this device */
146
147                 handler_desc = object->device.handler;
148                 while (handler_desc) {
149                         next_desc = handler_desc->address_space.next;
150                         acpi_ut_remove_reference(handler_desc);
151                         handler_desc = next_desc;
152                 }
153                 break;
154
155         case ACPI_TYPE_MUTEX:
156
157                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
158                                   "***** Mutex %p, OS Mutex %p\n",
159                                   object, object->mutex.os_mutex));
160
161                 if (object == acpi_gbl_global_lock_mutex) {
162
163                         /* Global Lock has extra semaphore */
164
165                         (void)
166                             acpi_os_delete_semaphore
167                             (acpi_gbl_global_lock_semaphore);
168                         acpi_gbl_global_lock_semaphore = NULL;
169
170                         acpi_os_delete_mutex(object->mutex.os_mutex);
171                         acpi_gbl_global_lock_mutex = NULL;
172                 } else {
173                         acpi_ex_unlink_mutex(object);
174                         acpi_os_delete_mutex(object->mutex.os_mutex);
175                 }
176                 break;
177
178         case ACPI_TYPE_EVENT:
179
180                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
181                                   "***** Event %p, OS Semaphore %p\n",
182                                   object, object->event.os_semaphore));
183
184                 (void)acpi_os_delete_semaphore(object->event.os_semaphore);
185                 object->event.os_semaphore = NULL;
186                 break;
187
188         case ACPI_TYPE_METHOD:
189
190                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
191                                   "***** Method %p\n", object));
192
193                 /* Delete the method mutex if it exists */
194
195                 if (object->method.mutex) {
196                         acpi_os_delete_mutex(object->method.mutex->mutex.
197                                              os_mutex);
198                         acpi_ut_delete_object_desc(object->method.mutex);
199                         object->method.mutex = NULL;
200                 }
201                 break;
202
203         case ACPI_TYPE_REGION:
204
205                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
206                                   "***** Region %p\n", object));
207
208                 second_desc = acpi_ns_get_secondary_object(object);
209                 if (second_desc) {
210                         /*
211                          * Free the region_context if and only if the handler is one of the
212                          * default handlers -- and therefore, we created the context object
213                          * locally, it was not created by an external caller.
214                          */
215                         handler_desc = object->region.handler;
216                         if (handler_desc) {
217                                 if (handler_desc->address_space.handler_flags &
218                                     ACPI_ADDR_HANDLER_DEFAULT_INSTALLED) {
219
220                                         /* Deactivate region and free region context */
221
222                                         if (handler_desc->address_space.setup) {
223                                                 (void)handler_desc->
224                                                     address_space.setup(object,
225                                                                         ACPI_REGION_DEACTIVATE,
226                                                                         handler_desc->
227                                                                         address_space.
228                                                                         context,
229                                                                         &second_desc->
230                                                                         extra.
231                                                                         region_context);
232                                         }
233                                 }
234
235                                 acpi_ut_remove_reference(handler_desc);
236                         }
237
238                         /* Now we can free the Extra object */
239
240                         acpi_ut_delete_object_desc(second_desc);
241                 }
242                 break;
243
244         case ACPI_TYPE_BUFFER_FIELD:
245
246                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
247                                   "***** Buffer Field %p\n", object));
248
249                 second_desc = acpi_ns_get_secondary_object(object);
250                 if (second_desc) {
251                         acpi_ut_delete_object_desc(second_desc);
252                 }
253                 break;
254
255         case ACPI_TYPE_LOCAL_BANK_FIELD:
256
257                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
258                                   "***** Bank Field %p\n", object));
259
260                 second_desc = acpi_ns_get_secondary_object(object);
261                 if (second_desc) {
262                         acpi_ut_delete_object_desc(second_desc);
263                 }
264                 break;
265
266         default:
267                 break;
268         }
269
270         /* Free any allocated memory (pointer within the object) found above */
271
272         if (obj_pointer) {
273                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
274                                   "Deleting Object Subptr %p\n", obj_pointer));
275                 ACPI_FREE(obj_pointer);
276         }
277
278         /* Now the object can be safely deleted */
279
280         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS, "Deleting Object %p [%s]\n",
281                           object, acpi_ut_get_object_type_name(object)));
282
283         acpi_ut_delete_object_desc(object);
284         return_VOID;
285 }
286
287 /*******************************************************************************
288  *
289  * FUNCTION:    acpi_ut_delete_internal_object_list
290  *
291  * PARAMETERS:  obj_list        - Pointer to the list to be deleted
292  *
293  * RETURN:      None
294  *
295  * DESCRIPTION: This function deletes an internal object list, including both
296  *              simple objects and package objects
297  *
298  ******************************************************************************/
299
300 void acpi_ut_delete_internal_object_list(union acpi_operand_object **obj_list)
301 {
302         union acpi_operand_object **internal_obj;
303
304         ACPI_FUNCTION_TRACE(ut_delete_internal_object_list);
305
306         /* Walk the null-terminated internal list */
307
308         for (internal_obj = obj_list; *internal_obj; internal_obj++) {
309                 acpi_ut_remove_reference(*internal_obj);
310         }
311
312         /* Free the combined parameter pointer list and object array */
313
314         ACPI_FREE(obj_list);
315         return_VOID;
316 }
317
318 /*******************************************************************************
319  *
320  * FUNCTION:    acpi_ut_update_ref_count
321  *
322  * PARAMETERS:  Object          - Object whose ref count is to be updated
323  *              Action          - What to do
324  *
325  * RETURN:      New ref count
326  *
327  * DESCRIPTION: Modify the ref count and return it.
328  *
329  ******************************************************************************/
330
331 static void
332 acpi_ut_update_ref_count(union acpi_operand_object *object, u32 action)
333 {
334         u16 count;
335         u16 new_count;
336
337         ACPI_FUNCTION_NAME(ut_update_ref_count);
338
339         if (!object) {
340                 return;
341         }
342
343         count = object->common.reference_count;
344         new_count = count;
345
346         /*
347          * Perform the reference count action (increment, decrement, force delete)
348          */
349         switch (action) {
350         case REF_INCREMENT:
351
352                 new_count++;
353                 object->common.reference_count = new_count;
354
355                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
356                                   "Obj %p Refs=%X, [Incremented]\n",
357                                   object, new_count));
358                 break;
359
360         case REF_DECREMENT:
361
362                 if (count < 1) {
363                         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
364                                           "Obj %p Refs=%X, can't decrement! (Set to 0)\n",
365                                           object, new_count));
366
367                         new_count = 0;
368                 } else {
369                         new_count--;
370
371                         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
372                                           "Obj %p Refs=%X, [Decremented]\n",
373                                           object, new_count));
374                 }
375
376                 if (ACPI_GET_OBJECT_TYPE(object) == ACPI_TYPE_METHOD) {
377                         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
378                                           "Method Obj %p Refs=%X, [Decremented]\n",
379                                           object, new_count));
380                 }
381
382                 object->common.reference_count = new_count;
383                 if (new_count == 0) {
384                         acpi_ut_delete_internal_obj(object);
385                 }
386                 break;
387
388         case REF_FORCE_DELETE:
389
390                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
391                                   "Obj %p Refs=%X, Force delete! (Set to 0)\n",
392                                   object, count));
393
394                 new_count = 0;
395                 object->common.reference_count = new_count;
396                 acpi_ut_delete_internal_obj(object);
397                 break;
398
399         default:
400
401                 ACPI_ERROR((AE_INFO, "Unknown action (%X)", action));
402                 break;
403         }
404
405         /*
406          * Sanity check the reference count, for debug purposes only.
407          * (A deleted object will have a huge reference count)
408          */
409         if (count > ACPI_MAX_REFERENCE_COUNT) {
410                 ACPI_WARNING((AE_INFO,
411                               "Large Reference Count (%X) in object %p", count,
412                               object));
413         }
414 }
415
416 /*******************************************************************************
417  *
418  * FUNCTION:    acpi_ut_update_object_reference
419  *
420  * PARAMETERS:  Object              - Increment ref count for this object
421  *                                    and all sub-objects
422  *              Action              - Either REF_INCREMENT or REF_DECREMENT or
423  *                                    REF_FORCE_DELETE
424  *
425  * RETURN:      Status
426  *
427  * DESCRIPTION: Increment the object reference count
428  *
429  * Object references are incremented when:
430  * 1) An object is attached to a Node (namespace object)
431  * 2) An object is copied (all subobjects must be incremented)
432  *
433  * Object references are decremented when:
434  * 1) An object is detached from an Node
435  *
436  ******************************************************************************/
437
438 acpi_status
439 acpi_ut_update_object_reference(union acpi_operand_object *object, u16 action)
440 {
441         acpi_status status = AE_OK;
442         union acpi_generic_state *state_list = NULL;
443         union acpi_operand_object *next_object = NULL;
444         union acpi_generic_state *state;
445         u32 i;
446
447         ACPI_FUNCTION_TRACE_PTR(ut_update_object_reference, object);
448
449         while (object) {
450
451                 /* Make sure that this isn't a namespace handle */
452
453                 if (ACPI_GET_DESCRIPTOR_TYPE(object) == ACPI_DESC_TYPE_NAMED) {
454                         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
455                                           "Object %p is NS handle\n", object));
456                         return_ACPI_STATUS(AE_OK);
457                 }
458
459                 /*
460                  * All sub-objects must have their reference count incremented also.
461                  * Different object types have different subobjects.
462                  */
463                 switch (ACPI_GET_OBJECT_TYPE(object)) {
464                 case ACPI_TYPE_DEVICE:
465                 case ACPI_TYPE_PROCESSOR:
466                 case ACPI_TYPE_POWER:
467                 case ACPI_TYPE_THERMAL:
468
469                         /* Update the notify objects for these types (if present) */
470
471                         acpi_ut_update_ref_count(object->common_notify.
472                                                  system_notify, action);
473                         acpi_ut_update_ref_count(object->common_notify.
474                                                  device_notify, action);
475                         break;
476
477                 case ACPI_TYPE_PACKAGE:
478                         /*
479                          * We must update all the sub-objects of the package,
480                          * each of whom may have their own sub-objects.
481                          */
482                         for (i = 0; i < object->package.count; i++) {
483                                 /*
484                                  * Push each element onto the stack for later processing.
485                                  * Note: There can be null elements within the package,
486                                  * these are simply ignored
487                                  */
488                                 status =
489                                     acpi_ut_create_update_state_and_push
490                                     (object->package.elements[i], action,
491                                      &state_list);
492                                 if (ACPI_FAILURE(status)) {
493                                         goto error_exit;
494                                 }
495                         }
496                         break;
497
498                 case ACPI_TYPE_BUFFER_FIELD:
499
500                         next_object = object->buffer_field.buffer_obj;
501                         break;
502
503                 case ACPI_TYPE_LOCAL_REGION_FIELD:
504
505                         next_object = object->field.region_obj;
506                         break;
507
508                 case ACPI_TYPE_LOCAL_BANK_FIELD:
509
510                         next_object = object->bank_field.bank_obj;
511                         status =
512                             acpi_ut_create_update_state_and_push(object->
513                                                                  bank_field.
514                                                                  region_obj,
515                                                                  action,
516                                                                  &state_list);
517                         if (ACPI_FAILURE(status)) {
518                                 goto error_exit;
519                         }
520                         break;
521
522                 case ACPI_TYPE_LOCAL_INDEX_FIELD:
523
524                         next_object = object->index_field.index_obj;
525                         status =
526                             acpi_ut_create_update_state_and_push(object->
527                                                                  index_field.
528                                                                  data_obj,
529                                                                  action,
530                                                                  &state_list);
531                         if (ACPI_FAILURE(status)) {
532                                 goto error_exit;
533                         }
534                         break;
535
536                 case ACPI_TYPE_LOCAL_REFERENCE:
537                         /*
538                          * The target of an Index (a package, string, or buffer) or a named
539                          * reference must track changes to the ref count of the index or
540                          * target object.
541                          */
542                         if ((object->reference.opcode == AML_INDEX_OP) ||
543                             (object->reference.opcode == AML_INT_NAMEPATH_OP)) {
544                                 next_object = object->reference.object;
545                         }
546                         break;
547
548                 case ACPI_TYPE_REGION:
549                 default:
550                         break;  /* No subobjects for all other types */
551                 }
552
553                 /*
554                  * Now we can update the count in the main object. This can only
555                  * happen after we update the sub-objects in case this causes the
556                  * main object to be deleted.
557                  */
558                 acpi_ut_update_ref_count(object, action);
559                 object = NULL;
560
561                 /* Move on to the next object to be updated */
562
563                 if (next_object) {
564                         object = next_object;
565                         next_object = NULL;
566                 } else if (state_list) {
567                         state = acpi_ut_pop_generic_state(&state_list);
568                         object = state->update.object;
569                         acpi_ut_delete_generic_state(state);
570                 }
571         }
572
573         return_ACPI_STATUS(AE_OK);
574
575       error_exit:
576
577         ACPI_EXCEPTION((AE_INFO, status,
578                         "Could not update object reference count"));
579
580         return_ACPI_STATUS(status);
581 }
582
583 /*******************************************************************************
584  *
585  * FUNCTION:    acpi_ut_add_reference
586  *
587  * PARAMETERS:  Object          - Object whose reference count is to be
588  *                                incremented
589  *
590  * RETURN:      None
591  *
592  * DESCRIPTION: Add one reference to an ACPI object
593  *
594  ******************************************************************************/
595
596 void acpi_ut_add_reference(union acpi_operand_object *object)
597 {
598
599         ACPI_FUNCTION_TRACE_PTR(ut_add_reference, object);
600
601         /* Ensure that we have a valid object */
602
603         if (!acpi_ut_valid_internal_object(object)) {
604                 return_VOID;
605         }
606
607         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
608                           "Obj %p Current Refs=%X [To Be Incremented]\n",
609                           object, object->common.reference_count));
610
611         /* Increment the reference count */
612
613         (void)acpi_ut_update_object_reference(object, REF_INCREMENT);
614         return_VOID;
615 }
616
617 /*******************************************************************************
618  *
619  * FUNCTION:    acpi_ut_remove_reference
620  *
621  * PARAMETERS:  Object         - Object whose ref count will be decremented
622  *
623  * RETURN:      None
624  *
625  * DESCRIPTION: Decrement the reference count of an ACPI internal object
626  *
627  ******************************************************************************/
628
629 void acpi_ut_remove_reference(union acpi_operand_object *object)
630 {
631
632         ACPI_FUNCTION_TRACE_PTR(ut_remove_reference, object);
633
634         /*
635          * Allow a NULL pointer to be passed in, just ignore it. This saves
636          * each caller from having to check. Also, ignore NS nodes.
637          *
638          */
639         if (!object ||
640             (ACPI_GET_DESCRIPTOR_TYPE(object) == ACPI_DESC_TYPE_NAMED)) {
641                 return_VOID;
642         }
643
644         /* Ensure that we have a valid object */
645
646         if (!acpi_ut_valid_internal_object(object)) {
647                 return_VOID;
648         }
649
650         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
651                           "Obj %p Current Refs=%X [To Be Decremented]\n",
652                           object, object->common.reference_count));
653
654         /*
655          * Decrement the reference count, and only actually delete the object
656          * if the reference count becomes 0. (Must also decrement the ref count
657          * of all subobjects!)
658          */
659         (void)acpi_ut_update_object_reference(object, REF_DECREMENT);
660         return_VOID;
661 }