Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
[linux-2.6] / drivers / acpi / acpica / nsalloc.c
1 /*******************************************************************************
2  *
3  * Module Name: nsalloc - Namespace allocation and deletion 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 "accommon.h"
46 #include "acnamesp.h"
47
48 #define _COMPONENT          ACPI_NAMESPACE
49 ACPI_MODULE_NAME("nsalloc")
50
51 /*******************************************************************************
52  *
53  * FUNCTION:    acpi_ns_create_node
54  *
55  * PARAMETERS:  Name            - Name of the new node (4 char ACPI name)
56  *
57  * RETURN:      New namespace node (Null on failure)
58  *
59  * DESCRIPTION: Create a namespace node
60  *
61  ******************************************************************************/
62 struct acpi_namespace_node *acpi_ns_create_node(u32 name)
63 {
64         struct acpi_namespace_node *node;
65 #ifdef ACPI_DBG_TRACK_ALLOCATIONS
66         u32 temp;
67 #endif
68
69         ACPI_FUNCTION_TRACE(ns_create_node);
70
71         node = acpi_os_acquire_object(acpi_gbl_namespace_cache);
72         if (!node) {
73                 return_PTR(NULL);
74         }
75
76         ACPI_MEM_TRACKING(acpi_gbl_ns_node_list->total_allocated++);
77
78 #ifdef ACPI_DBG_TRACK_ALLOCATIONS
79         temp = acpi_gbl_ns_node_list->total_allocated -
80             acpi_gbl_ns_node_list->total_freed;
81         if (temp > acpi_gbl_ns_node_list->max_occupied) {
82                 acpi_gbl_ns_node_list->max_occupied = temp;
83         }
84 #endif
85
86         node->name.integer = name;
87         ACPI_SET_DESCRIPTOR_TYPE(node, ACPI_DESC_TYPE_NAMED);
88         return_PTR(node);
89 }
90
91 /*******************************************************************************
92  *
93  * FUNCTION:    acpi_ns_delete_node
94  *
95  * PARAMETERS:  Node            - Node to be deleted
96  *
97  * RETURN:      None
98  *
99  * DESCRIPTION: Delete a namespace node
100  *
101  ******************************************************************************/
102
103 void acpi_ns_delete_node(struct acpi_namespace_node *node)
104 {
105         struct acpi_namespace_node *parent_node;
106         struct acpi_namespace_node *prev_node;
107         struct acpi_namespace_node *next_node;
108
109         ACPI_FUNCTION_TRACE_PTR(ns_delete_node, node);
110
111         parent_node = acpi_ns_get_parent_node(node);
112
113         prev_node = NULL;
114         next_node = parent_node->child;
115
116         /* Find the node that is the previous peer in the parent's child list */
117
118         while (next_node != node) {
119                 prev_node = next_node;
120                 next_node = prev_node->peer;
121         }
122
123         if (prev_node) {
124
125                 /* Node is not first child, unlink it */
126
127                 prev_node->peer = next_node->peer;
128                 if (next_node->flags & ANOBJ_END_OF_PEER_LIST) {
129                         prev_node->flags |= ANOBJ_END_OF_PEER_LIST;
130                 }
131         } else {
132                 /* Node is first child (has no previous peer) */
133
134                 if (next_node->flags & ANOBJ_END_OF_PEER_LIST) {
135
136                         /* No peers at all */
137
138                         parent_node->child = NULL;
139                 } else {        /* Link peer list to parent */
140
141                         parent_node->child = next_node->peer;
142                 }
143         }
144
145         ACPI_MEM_TRACKING(acpi_gbl_ns_node_list->total_freed++);
146
147         /* Detach an object if there is one, then delete the node */
148
149         acpi_ns_detach_object(node);
150         (void)acpi_os_release_object(acpi_gbl_namespace_cache, node);
151         return_VOID;
152 }
153
154 /*******************************************************************************
155  *
156  * FUNCTION:    acpi_ns_install_node
157  *
158  * PARAMETERS:  walk_state      - Current state of the walk
159  *              parent_node     - The parent of the new Node
160  *              Node            - The new Node to install
161  *              Type            - ACPI object type of the new Node
162  *
163  * RETURN:      None
164  *
165  * DESCRIPTION: Initialize a new namespace node and install it amongst
166  *              its peers.
167  *
168  *              Note: Current namespace lookup is linear search. This appears
169  *              to be sufficient as namespace searches consume only a small
170  *              fraction of the execution time of the ACPI subsystem.
171  *
172  ******************************************************************************/
173
174 void acpi_ns_install_node(struct acpi_walk_state *walk_state, struct acpi_namespace_node *parent_node,  /* Parent */
175                           struct acpi_namespace_node *node,     /* New Child */
176                           acpi_object_type type)
177 {
178         acpi_owner_id owner_id = 0;
179         struct acpi_namespace_node *child_node;
180
181         ACPI_FUNCTION_TRACE(ns_install_node);
182
183         /*
184          * Get the owner ID from the Walk state. The owner ID is used to track
185          * table deletion and deletion of objects created by methods.
186          */
187         if (walk_state) {
188                 owner_id = walk_state->owner_id;
189         }
190
191         /* Link the new entry into the parent and existing children */
192
193         child_node = parent_node->child;
194         if (!child_node) {
195                 parent_node->child = node;
196                 node->flags |= ANOBJ_END_OF_PEER_LIST;
197                 node->peer = parent_node;
198         } else {
199                 while (!(child_node->flags & ANOBJ_END_OF_PEER_LIST)) {
200                         child_node = child_node->peer;
201                 }
202
203                 child_node->peer = node;
204
205                 /* Clear end-of-list flag */
206
207                 child_node->flags &= ~ANOBJ_END_OF_PEER_LIST;
208                 node->flags |= ANOBJ_END_OF_PEER_LIST;
209                 node->peer = parent_node;
210         }
211
212         /* Init the new entry */
213
214         node->owner_id = owner_id;
215         node->type = (u8) type;
216
217         ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
218                           "%4.4s (%s) [Node %p Owner %X] added to %4.4s (%s) [Node %p]\n",
219                           acpi_ut_get_node_name(node),
220                           acpi_ut_get_type_name(node->type), node, owner_id,
221                           acpi_ut_get_node_name(parent_node),
222                           acpi_ut_get_type_name(parent_node->type),
223                           parent_node));
224
225         return_VOID;
226 }
227
228 /*******************************************************************************
229  *
230  * FUNCTION:    acpi_ns_delete_children
231  *
232  * PARAMETERS:  parent_node     - Delete this objects children
233  *
234  * RETURN:      None.
235  *
236  * DESCRIPTION: Delete all children of the parent object. In other words,
237  *              deletes a "scope".
238  *
239  ******************************************************************************/
240
241 void acpi_ns_delete_children(struct acpi_namespace_node *parent_node)
242 {
243         struct acpi_namespace_node *child_node;
244         struct acpi_namespace_node *next_node;
245         u8 flags;
246
247         ACPI_FUNCTION_TRACE_PTR(ns_delete_children, parent_node);
248
249         if (!parent_node) {
250                 return_VOID;
251         }
252
253         /* If no children, all done! */
254
255         child_node = parent_node->child;
256         if (!child_node) {
257                 return_VOID;
258         }
259
260         /* Deallocate all children at this level */
261
262         do {
263
264                 /* Get the things we need */
265
266                 next_node = child_node->peer;
267                 flags = child_node->flags;
268
269                 /* Grandchildren should have all been deleted already */
270
271                 if (child_node->child) {
272                         ACPI_ERROR((AE_INFO, "Found a grandchild! P=%p C=%p",
273                                     parent_node, child_node));
274                 }
275
276                 /* Now we can free this child object */
277
278                 ACPI_MEM_TRACKING(acpi_gbl_ns_node_list->total_freed++);
279
280                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
281                                   "Object %p, Remaining %X\n", child_node,
282                                   acpi_gbl_current_node_count));
283
284                 /* Detach an object if there is one, then free the child node */
285
286                 acpi_ns_detach_object(child_node);
287
288                 /* Now we can delete the node */
289
290                 (void)acpi_os_release_object(acpi_gbl_namespace_cache,
291                                              child_node);
292
293                 /* And move on to the next child in the list */
294
295                 child_node = next_node;
296
297         } while (!(flags & ANOBJ_END_OF_PEER_LIST));
298
299         /* Clear the parent's child pointer */
300
301         parent_node->child = NULL;
302         return_VOID;
303 }
304
305 /*******************************************************************************
306  *
307  * FUNCTION:    acpi_ns_delete_namespace_subtree
308  *
309  * PARAMETERS:  parent_node     - Root of the subtree to be deleted
310  *
311  * RETURN:      None.
312  *
313  * DESCRIPTION: Delete a subtree of the namespace.  This includes all objects
314  *              stored within the subtree.
315  *
316  ******************************************************************************/
317
318 void acpi_ns_delete_namespace_subtree(struct acpi_namespace_node *parent_node)
319 {
320         struct acpi_namespace_node *child_node = NULL;
321         u32 level = 1;
322
323         ACPI_FUNCTION_TRACE(ns_delete_namespace_subtree);
324
325         if (!parent_node) {
326                 return_VOID;
327         }
328
329         /*
330          * Traverse the tree of objects until we bubble back up
331          * to where we started.
332          */
333         while (level > 0) {
334
335                 /* Get the next node in this scope (NULL if none) */
336
337                 child_node = acpi_ns_get_next_node(parent_node, child_node);
338                 if (child_node) {
339
340                         /* Found a child node - detach any attached object */
341
342                         acpi_ns_detach_object(child_node);
343
344                         /* Check if this node has any children */
345
346                         if (child_node->child) {
347                                 /*
348                                  * There is at least one child of this node,
349                                  * visit the node
350                                  */
351                                 level++;
352                                 parent_node = child_node;
353                                 child_node = NULL;
354                         }
355                 } else {
356                         /*
357                          * No more children of this parent node.
358                          * Move up to the grandparent.
359                          */
360                         level--;
361
362                         /*
363                          * Now delete all of the children of this parent
364                          * all at the same time.
365                          */
366                         acpi_ns_delete_children(parent_node);
367
368                         /* New "last child" is this parent node */
369
370                         child_node = parent_node;
371
372                         /* Move up the tree to the grandparent */
373
374                         parent_node = acpi_ns_get_parent_node(parent_node);
375                 }
376         }
377
378         return_VOID;
379 }
380
381 /*******************************************************************************
382  *
383  * FUNCTION:    acpi_ns_delete_namespace_by_owner
384  *
385  * PARAMETERS:  owner_id    - All nodes with this owner will be deleted
386  *
387  * RETURN:      Status
388  *
389  * DESCRIPTION: Delete entries within the namespace that are owned by a
390  *              specific ID.  Used to delete entire ACPI tables.  All
391  *              reference counts are updated.
392  *
393  * MUTEX:       Locks namespace during deletion walk.
394  *
395  ******************************************************************************/
396
397 void acpi_ns_delete_namespace_by_owner(acpi_owner_id owner_id)
398 {
399         struct acpi_namespace_node *child_node;
400         struct acpi_namespace_node *deletion_node;
401         struct acpi_namespace_node *parent_node;
402         u32 level;
403         acpi_status status;
404
405         ACPI_FUNCTION_TRACE_U32(ns_delete_namespace_by_owner, owner_id);
406
407         if (owner_id == 0) {
408                 return_VOID;
409         }
410
411         /* Lock namespace for possible update */
412
413         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
414         if (ACPI_FAILURE(status)) {
415                 return_VOID;
416         }
417
418         deletion_node = NULL;
419         parent_node = acpi_gbl_root_node;
420         child_node = NULL;
421         level = 1;
422
423         /*
424          * Traverse the tree of nodes until we bubble back up
425          * to where we started.
426          */
427         while (level > 0) {
428                 /*
429                  * Get the next child of this parent node. When child_node is NULL,
430                  * the first child of the parent is returned
431                  */
432                 child_node = acpi_ns_get_next_node(parent_node, child_node);
433
434                 if (deletion_node) {
435                         acpi_ns_delete_children(deletion_node);
436                         acpi_ns_delete_node(deletion_node);
437                         deletion_node = NULL;
438                 }
439
440                 if (child_node) {
441                         if (child_node->owner_id == owner_id) {
442
443                                 /* Found a matching child node - detach any attached object */
444
445                                 acpi_ns_detach_object(child_node);
446                         }
447
448                         /* Check if this node has any children */
449
450                         if (child_node->child) {
451                                 /*
452                                  * There is at least one child of this node,
453                                  * visit the node
454                                  */
455                                 level++;
456                                 parent_node = child_node;
457                                 child_node = NULL;
458                         } else if (child_node->owner_id == owner_id) {
459                                 deletion_node = child_node;
460                         }
461                 } else {
462                         /*
463                          * No more children of this parent node.
464                          * Move up to the grandparent.
465                          */
466                         level--;
467                         if (level != 0) {
468                                 if (parent_node->owner_id == owner_id) {
469                                         deletion_node = parent_node;
470                                 }
471                         }
472
473                         /* New "last child" is this parent node */
474
475                         child_node = parent_node;
476
477                         /* Move up the tree to the grandparent */
478
479                         parent_node = acpi_ns_get_parent_node(parent_node);
480                 }
481         }
482
483         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
484         return_VOID;
485 }