Merge git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-linus
[sfrench/cifs-2.6.git] / 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 =
80             acpi_gbl_ns_node_list->total_allocated -
81             acpi_gbl_ns_node_list->total_freed;
82         if (temp > acpi_gbl_ns_node_list->max_occupied) {
83                 acpi_gbl_ns_node_list->max_occupied = temp;
84         }
85 #endif
86
87         node->name.integer = name;
88         ACPI_SET_DESCRIPTOR_TYPE(node, ACPI_DESC_TYPE_NAMED);
89         return_PTR(node);
90 }
91
92 /*******************************************************************************
93  *
94  * FUNCTION:    acpi_ns_delete_node
95  *
96  * PARAMETERS:  Node            - Node to be deleted
97  *
98  * RETURN:      None
99  *
100  * DESCRIPTION: Delete a namespace node
101  *
102  ******************************************************************************/
103
104 void acpi_ns_delete_node(struct acpi_namespace_node *node)
105 {
106         struct acpi_namespace_node *parent_node;
107         struct acpi_namespace_node *prev_node;
108         struct acpi_namespace_node *next_node;
109
110         ACPI_FUNCTION_TRACE_PTR(ns_delete_node, node);
111
112         parent_node = acpi_ns_get_parent_node(node);
113
114         prev_node = NULL;
115         next_node = parent_node->child;
116
117         /* Find the node that is the previous peer in the parent's child list */
118
119         while (next_node != node) {
120                 prev_node = next_node;
121                 next_node = prev_node->peer;
122         }
123
124         if (prev_node) {
125
126                 /* Node is not first child, unlink it */
127
128                 prev_node->peer = next_node->peer;
129                 if (next_node->flags & ANOBJ_END_OF_PEER_LIST) {
130                         prev_node->flags |= ANOBJ_END_OF_PEER_LIST;
131                 }
132         } else {
133                 /* Node is first child (has no previous peer) */
134
135                 if (next_node->flags & ANOBJ_END_OF_PEER_LIST) {
136
137                         /* No peers at all */
138
139                         parent_node->child = NULL;
140                 } else {        /* Link peer list to parent */
141
142                         parent_node->child = next_node->peer;
143                 }
144         }
145
146         ACPI_MEM_TRACKING(acpi_gbl_ns_node_list->total_freed++);
147
148         /*
149          * Detach an object if there is one, then delete the node
150          */
151         acpi_ns_detach_object(node);
152         (void)acpi_os_release_object(acpi_gbl_namespace_cache, node);
153         return_VOID;
154 }
155
156 /*******************************************************************************
157  *
158  * FUNCTION:    acpi_ns_install_node
159  *
160  * PARAMETERS:  walk_state      - Current state of the walk
161  *              parent_node     - The parent of the new Node
162  *              Node            - The new Node to install
163  *              Type            - ACPI object type of the new Node
164  *
165  * RETURN:      None
166  *
167  * DESCRIPTION: Initialize a new namespace node and install it amongst
168  *              its peers.
169  *
170  *              Note: Current namespace lookup is linear search. This appears
171  *              to be sufficient as namespace searches consume only a small
172  *              fraction of the execution time of the ACPI subsystem.
173  *
174  ******************************************************************************/
175
176 void acpi_ns_install_node(struct acpi_walk_state *walk_state, struct acpi_namespace_node *parent_node,  /* Parent */
177                           struct acpi_namespace_node *node,     /* New Child */
178                           acpi_object_type type)
179 {
180         acpi_owner_id owner_id = 0;
181         struct acpi_namespace_node *child_node;
182
183         ACPI_FUNCTION_TRACE(ns_install_node);
184
185         /*
186          * Get the owner ID from the Walk state
187          * The owner ID is used to track table deletion and
188          * deletion of objects created by methods
189          */
190         if (walk_state) {
191                 owner_id = walk_state->owner_id;
192         }
193
194         /* Link the new entry into the parent and existing children */
195
196         child_node = parent_node->child;
197         if (!child_node) {
198                 parent_node->child = node;
199                 node->flags |= ANOBJ_END_OF_PEER_LIST;
200                 node->peer = parent_node;
201         } else {
202                 while (!(child_node->flags & ANOBJ_END_OF_PEER_LIST)) {
203                         child_node = child_node->peer;
204                 }
205
206                 child_node->peer = node;
207
208                 /* Clear end-of-list flag */
209
210                 child_node->flags &= ~ANOBJ_END_OF_PEER_LIST;
211                 node->flags |= ANOBJ_END_OF_PEER_LIST;
212                 node->peer = parent_node;
213         }
214
215         /* Init the new entry */
216
217         node->owner_id = owner_id;
218         node->type = (u8) type;
219
220         ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
221                           "%4.4s (%s) [Node %p Owner %X] added to %4.4s (%s) [Node %p]\n",
222                           acpi_ut_get_node_name(node),
223                           acpi_ut_get_type_name(node->type), node, owner_id,
224                           acpi_ut_get_node_name(parent_node),
225                           acpi_ut_get_type_name(parent_node->type),
226                           parent_node));
227
228         return_VOID;
229 }
230
231 /*******************************************************************************
232  *
233  * FUNCTION:    acpi_ns_delete_children
234  *
235  * PARAMETERS:  parent_node     - Delete this objects children
236  *
237  * RETURN:      None.
238  *
239  * DESCRIPTION: Delete all children of the parent object. In other words,
240  *              deletes a "scope".
241  *
242  ******************************************************************************/
243
244 void acpi_ns_delete_children(struct acpi_namespace_node *parent_node)
245 {
246         struct acpi_namespace_node *child_node;
247         struct acpi_namespace_node *next_node;
248         u8 flags;
249
250         ACPI_FUNCTION_TRACE_PTR(ns_delete_children, parent_node);
251
252         if (!parent_node) {
253                 return_VOID;
254         }
255
256         /* If no children, all done! */
257
258         child_node = parent_node->child;
259         if (!child_node) {
260                 return_VOID;
261         }
262
263         /*
264          * Deallocate all children at this level
265          */
266         do {
267
268                 /* Get the things we need */
269
270                 next_node = child_node->peer;
271                 flags = child_node->flags;
272
273                 /* Grandchildren should have all been deleted already */
274
275                 if (child_node->child) {
276                         ACPI_ERROR((AE_INFO, "Found a grandchild! P=%p C=%p",
277                                     parent_node, child_node));
278                 }
279
280                 /* Now we can free this child object */
281
282                 ACPI_MEM_TRACKING(acpi_gbl_ns_node_list->total_freed++);
283
284                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
285                                   "Object %p, Remaining %X\n", child_node,
286                                   acpi_gbl_current_node_count));
287
288                 /*
289                  * Detach an object if there is one, then free the child node
290                  */
291                 acpi_ns_detach_object(child_node);
292
293                 /* Now we can delete the node */
294
295                 (void)acpi_os_release_object(acpi_gbl_namespace_cache,
296                                              child_node);
297
298                 /* And move on to the next child in the list */
299
300                 child_node = next_node;
301
302         } while (!(flags & ANOBJ_END_OF_PEER_LIST));
303
304         /* Clear the parent's child pointer */
305
306         parent_node->child = NULL;
307
308         return_VOID;
309 }
310
311 /*******************************************************************************
312  *
313  * FUNCTION:    acpi_ns_delete_namespace_subtree
314  *
315  * PARAMETERS:  parent_node     - Root of the subtree to be deleted
316  *
317  * RETURN:      None.
318  *
319  * DESCRIPTION: Delete a subtree of the namespace.  This includes all objects
320  *              stored within the subtree.
321  *
322  ******************************************************************************/
323
324 void acpi_ns_delete_namespace_subtree(struct acpi_namespace_node *parent_node)
325 {
326         struct acpi_namespace_node *child_node = NULL;
327         u32 level = 1;
328
329         ACPI_FUNCTION_TRACE(ns_delete_namespace_subtree);
330
331         if (!parent_node) {
332                 return_VOID;
333         }
334
335         /*
336          * Traverse the tree of objects until we bubble back up
337          * to where we started.
338          */
339         while (level > 0) {
340
341                 /* Get the next node in this scope (NULL if none) */
342
343                 child_node =
344                     acpi_ns_get_next_node(ACPI_TYPE_ANY, parent_node,
345                                           child_node);
346                 if (child_node) {
347
348                         /* Found a child node - detach any attached object */
349
350                         acpi_ns_detach_object(child_node);
351
352                         /* Check if this node has any children */
353
354                         if (acpi_ns_get_next_node
355                             (ACPI_TYPE_ANY, child_node, NULL)) {
356                                 /*
357                                  * There is at least one child of this node,
358                                  * visit the node
359                                  */
360                                 level++;
361                                 parent_node = child_node;
362                                 child_node = NULL;
363                         }
364                 } else {
365                         /*
366                          * No more children of this parent node.
367                          * Move up to the grandparent.
368                          */
369                         level--;
370
371                         /*
372                          * Now delete all of the children of this parent
373                          * all at the same time.
374                          */
375                         acpi_ns_delete_children(parent_node);
376
377                         /* New "last child" is this parent node */
378
379                         child_node = parent_node;
380
381                         /* Move up the tree to the grandparent */
382
383                         parent_node = acpi_ns_get_parent_node(parent_node);
384                 }
385         }
386
387         return_VOID;
388 }
389
390 /*******************************************************************************
391  *
392  * FUNCTION:    acpi_ns_delete_namespace_by_owner
393  *
394  * PARAMETERS:  owner_id    - All nodes with this owner will be deleted
395  *
396  * RETURN:      Status
397  *
398  * DESCRIPTION: Delete entries within the namespace that are owned by a
399  *              specific ID.  Used to delete entire ACPI tables.  All
400  *              reference counts are updated.
401  *
402  * MUTEX:       Locks namespace during deletion walk.
403  *
404  ******************************************************************************/
405
406 void acpi_ns_delete_namespace_by_owner(acpi_owner_id owner_id)
407 {
408         struct acpi_namespace_node *child_node;
409         struct acpi_namespace_node *deletion_node;
410         struct acpi_namespace_node *parent_node;
411         u32 level;
412         acpi_status status;
413
414         ACPI_FUNCTION_TRACE_U32(ns_delete_namespace_by_owner, owner_id);
415
416         if (owner_id == 0) {
417                 return_VOID;
418         }
419
420         /* Lock namespace for possible update */
421
422         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
423         if (ACPI_FAILURE(status)) {
424                 return_VOID;
425         }
426
427         deletion_node = NULL;
428         parent_node = acpi_gbl_root_node;
429         child_node = NULL;
430         level = 1;
431
432         /*
433          * Traverse the tree of nodes until we bubble back up
434          * to where we started.
435          */
436         while (level > 0) {
437                 /*
438                  * Get the next child of this parent node. When child_node is NULL,
439                  * the first child of the parent is returned
440                  */
441                 child_node =
442                     acpi_ns_get_next_node(ACPI_TYPE_ANY, parent_node,
443                                           child_node);
444
445                 if (deletion_node) {
446                         acpi_ns_delete_children(deletion_node);
447                         acpi_ns_delete_node(deletion_node);
448                         deletion_node = NULL;
449                 }
450
451                 if (child_node) {
452                         if (child_node->owner_id == owner_id) {
453
454                                 /* Found a matching child node - detach any attached object */
455
456                                 acpi_ns_detach_object(child_node);
457                         }
458
459                         /* Check if this node has any children */
460
461                         if (acpi_ns_get_next_node
462                             (ACPI_TYPE_ANY, child_node, NULL)) {
463                                 /*
464                                  * There is at least one child of this node,
465                                  * visit the node
466                                  */
467                                 level++;
468                                 parent_node = child_node;
469                                 child_node = NULL;
470                         } else if (child_node->owner_id == owner_id) {
471                                 deletion_node = child_node;
472                         }
473                 } else {
474                         /*
475                          * No more children of this parent node.
476                          * Move up to the grandparent.
477                          */
478                         level--;
479                         if (level != 0) {
480                                 if (parent_node->owner_id == owner_id) {
481                                         deletion_node = parent_node;
482                                 }
483                         }
484
485                         /* New "last child" is this parent node */
486
487                         child_node = parent_node;
488
489                         /* Move up the tree to the grandparent */
490
491                         parent_node = acpi_ns_get_parent_node(parent_node);
492                 }
493         }
494
495         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
496         return_VOID;
497 }