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1da177e4 LT |
1 | /****************************************************************************** |
2 | * | |
3 | * Module Name: nswalk - Functions for walking the ACPI namespace | |
4 | * | |
5 | *****************************************************************************/ | |
6 | ||
7 | /* | |
77848130 | 8 | * Copyright (C) 2000 - 2012, Intel Corp. |
1da177e4 LT |
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 | ||
1da177e4 | 44 | #include <acpi/acpi.h> |
e2f7a777 LB |
45 | #include "accommon.h" |
46 | #include "acnamesp.h" | |
1da177e4 | 47 | |
1da177e4 | 48 | #define _COMPONENT ACPI_NAMESPACE |
4be44fcd | 49 | ACPI_MODULE_NAME("nswalk") |
1da177e4 LT |
50 | |
51 | /******************************************************************************* | |
52 | * | |
53 | * FUNCTION: acpi_ns_get_next_node | |
54 | * | |
8c725bf9 | 55 | * PARAMETERS: parent_node - Parent node whose children we are |
44f6c012 | 56 | * getting |
1da177e4 LT |
57 | * child_node - Previous child that was found. |
58 | * The NEXT child will be returned | |
59 | * | |
60 | * RETURN: struct acpi_namespace_node - Pointer to the NEXT child or NULL if | |
61 | * none is found. | |
62 | * | |
73a3090a BM |
63 | * DESCRIPTION: Return the next peer node within the namespace. If Handle |
64 | * is valid, Scope is ignored. Otherwise, the first node | |
1da177e4 LT |
65 | * within Scope is returned. |
66 | * | |
67 | ******************************************************************************/ | |
8c725bf9 BM |
68 | struct acpi_namespace_node *acpi_ns_get_next_node(struct acpi_namespace_node |
69 | *parent_node, | |
70 | struct acpi_namespace_node | |
4be44fcd | 71 | *child_node) |
1da177e4 | 72 | { |
4be44fcd | 73 | ACPI_FUNCTION_ENTRY(); |
1da177e4 LT |
74 | |
75 | if (!child_node) { | |
52fc0b02 | 76 | |
1da177e4 LT |
77 | /* It's really the parent's _scope_ that we want */ |
78 | ||
8c725bf9 | 79 | return parent_node->child; |
1da177e4 LT |
80 | } |
81 | ||
8c725bf9 BM |
82 | /* Otherwise just return the next peer */ |
83 | ||
84 | return child_node->peer; | |
85 | } | |
86 | ||
87 | /******************************************************************************* | |
88 | * | |
89 | * FUNCTION: acpi_ns_get_next_node_typed | |
90 | * | |
ba494bee | 91 | * PARAMETERS: type - Type of node to be searched for |
8c725bf9 BM |
92 | * parent_node - Parent node whose children we are |
93 | * getting | |
94 | * child_node - Previous child that was found. | |
95 | * The NEXT child will be returned | |
96 | * | |
97 | * RETURN: struct acpi_namespace_node - Pointer to the NEXT child or NULL if | |
98 | * none is found. | |
99 | * | |
73a3090a BM |
100 | * DESCRIPTION: Return the next peer node within the namespace. If Handle |
101 | * is valid, Scope is ignored. Otherwise, the first node | |
8c725bf9 BM |
102 | * within Scope is returned. |
103 | * | |
104 | ******************************************************************************/ | |
105 | ||
106 | struct acpi_namespace_node *acpi_ns_get_next_node_typed(acpi_object_type type, | |
107 | struct | |
108 | acpi_namespace_node | |
109 | *parent_node, | |
110 | struct | |
111 | acpi_namespace_node | |
112 | *child_node) | |
113 | { | |
114 | struct acpi_namespace_node *next_node = NULL; | |
115 | ||
116 | ACPI_FUNCTION_ENTRY(); | |
117 | ||
118 | next_node = acpi_ns_get_next_node(parent_node, child_node); | |
119 | ||
120 | ||
1da177e4 LT |
121 | /* If any type is OK, we are done */ |
122 | ||
123 | if (type == ACPI_TYPE_ANY) { | |
52fc0b02 | 124 | |
1da177e4 LT |
125 | /* next_node is NULL if we are at the end-of-list */ |
126 | ||
127 | return (next_node); | |
128 | } | |
129 | ||
130 | /* Must search for the node -- but within this scope only */ | |
131 | ||
132 | while (next_node) { | |
52fc0b02 | 133 | |
1da177e4 LT |
134 | /* If type matches, we are done */ |
135 | ||
136 | if (next_node->type == type) { | |
137 | return (next_node); | |
138 | } | |
139 | ||
c45b5c09 | 140 | /* Otherwise, move on to the next peer node */ |
1da177e4 | 141 | |
c45b5c09 | 142 | next_node = next_node->peer; |
1da177e4 LT |
143 | } |
144 | ||
145 | /* Not found */ | |
146 | ||
147 | return (NULL); | |
148 | } | |
149 | ||
1da177e4 LT |
150 | /******************************************************************************* |
151 | * | |
152 | * FUNCTION: acpi_ns_walk_namespace | |
153 | * | |
ba494bee | 154 | * PARAMETERS: type - acpi_object_type to search for |
1da177e4 LT |
155 | * start_node - Handle in namespace where search begins |
156 | * max_depth - Depth to which search is to reach | |
ba494bee | 157 | * flags - Whether to unlock the NS before invoking |
1da177e4 | 158 | * the callback routine |
2263576c LM |
159 | * pre_order_visit - Called during tree pre-order visit |
160 | * when an object of "Type" is found | |
161 | * post_order_visit - Called during tree post-order visit | |
162 | * when an object of "Type" is found | |
ba494bee | 163 | * context - Passed to user function(s) above |
2263576c LM |
164 | * return_value - from the user_function if terminated |
165 | * early. Otherwise, returns NULL. | |
1da177e4 LT |
166 | * RETURNS: Status |
167 | * | |
168 | * DESCRIPTION: Performs a modified depth-first walk of the namespace tree, | |
169 | * starting (and ending) at the node specified by start_handle. | |
2263576c LM |
170 | * The callback function is called whenever a node that matches |
171 | * the type parameter is found. If the callback function returns | |
d4913dc6 BM |
172 | * a non-zero value, the search is terminated immediately and |
173 | * this value is returned to the caller. | |
1da177e4 LT |
174 | * |
175 | * The point of this procedure is to provide a generic namespace | |
176 | * walk routine that can be called from multiple places to | |
2263576c LM |
177 | * provide multiple services; the callback function(s) can be |
178 | * tailored to each task, whether it is a print function, | |
179 | * a compare function, etc. | |
1da177e4 LT |
180 | * |
181 | ******************************************************************************/ | |
182 | ||
183 | acpi_status | |
4be44fcd LB |
184 | acpi_ns_walk_namespace(acpi_object_type type, |
185 | acpi_handle start_node, | |
186 | u32 max_depth, | |
d1fdda83 | 187 | u32 flags, |
2263576c LM |
188 | acpi_walk_callback pre_order_visit, |
189 | acpi_walk_callback post_order_visit, | |
4be44fcd | 190 | void *context, void **return_value) |
1da177e4 | 191 | { |
4be44fcd LB |
192 | acpi_status status; |
193 | acpi_status mutex_status; | |
194 | struct acpi_namespace_node *child_node; | |
195 | struct acpi_namespace_node *parent_node; | |
196 | acpi_object_type child_type; | |
197 | u32 level; | |
2263576c | 198 | u8 node_previously_visited = FALSE; |
1da177e4 | 199 | |
b229cf92 | 200 | ACPI_FUNCTION_TRACE(ns_walk_namespace); |
1da177e4 LT |
201 | |
202 | /* Special case for the namespace Root Node */ | |
203 | ||
204 | if (start_node == ACPI_ROOT_OBJECT) { | |
205 | start_node = acpi_gbl_root_node; | |
206 | } | |
207 | ||
208 | /* Null child means "get first node" */ | |
209 | ||
210 | parent_node = start_node; | |
2263576c | 211 | child_node = acpi_ns_get_next_node(parent_node, NULL); |
4be44fcd LB |
212 | child_type = ACPI_TYPE_ANY; |
213 | level = 1; | |
1da177e4 LT |
214 | |
215 | /* | |
216 | * Traverse the tree of nodes until we bubble back up to where we | |
217 | * started. When Level is zero, the loop is done because we have | |
218 | * bubbled up to (and passed) the original parent handle (start_entry) | |
219 | */ | |
2263576c LM |
220 | while (level > 0 && child_node) { |
221 | status = AE_OK; | |
52fc0b02 | 222 | |
2263576c | 223 | /* Found next child, get the type if we are not searching for ANY */ |
1da177e4 | 224 | |
2263576c LM |
225 | if (type != ACPI_TYPE_ANY) { |
226 | child_type = child_node->type; | |
227 | } | |
3effba32 | 228 | |
2263576c LM |
229 | /* |
230 | * Ignore all temporary namespace nodes (created during control | |
231 | * method execution) unless told otherwise. These temporary nodes | |
232 | * can cause a race condition because they can be deleted during | |
233 | * the execution of the user function (if the namespace is | |
234 | * unlocked before invocation of the user function.) Only the | |
235 | * debugger namespace dump will examine the temporary nodes. | |
236 | */ | |
237 | if ((child_node->flags & ANOBJ_TEMPORARY) && | |
238 | !(flags & ACPI_NS_WALK_TEMP_NODES)) { | |
239 | status = AE_CTRL_DEPTH; | |
240 | } | |
3effba32 | 241 | |
2263576c | 242 | /* Type must match requested type */ |
1da177e4 | 243 | |
2263576c | 244 | else if (child_type == type) { |
3effba32 | 245 | /* |
2263576c LM |
246 | * Found a matching node, invoke the user callback function. |
247 | * Unlock the namespace if flag is set. | |
3effba32 | 248 | */ |
2263576c LM |
249 | if (flags & ACPI_NS_WALK_UNLOCK) { |
250 | mutex_status = | |
251 | acpi_ut_release_mutex(ACPI_MTX_NAMESPACE); | |
252 | if (ACPI_FAILURE(mutex_status)) { | |
253 | return_ACPI_STATUS(mutex_status); | |
254 | } | |
c1014629 BM |
255 | } |
256 | ||
2263576c LM |
257 | /* |
258 | * Invoke the user function, either pre-order or post-order | |
259 | * or both. | |
260 | */ | |
261 | if (!node_previously_visited) { | |
262 | if (pre_order_visit) { | |
263 | status = | |
264 | pre_order_visit(child_node, level, | |
265 | context, | |
266 | return_value); | |
1da177e4 | 267 | } |
2263576c LM |
268 | } else { |
269 | if (post_order_visit) { | |
270 | status = | |
271 | post_order_visit(child_node, level, | |
272 | context, | |
273 | return_value); | |
274 | } | |
275 | } | |
1da177e4 | 276 | |
2263576c LM |
277 | if (flags & ACPI_NS_WALK_UNLOCK) { |
278 | mutex_status = | |
279 | acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE); | |
280 | if (ACPI_FAILURE(mutex_status)) { | |
281 | return_ACPI_STATUS(mutex_status); | |
1da177e4 | 282 | } |
2263576c | 283 | } |
1da177e4 | 284 | |
2263576c LM |
285 | switch (status) { |
286 | case AE_OK: | |
287 | case AE_CTRL_DEPTH: | |
1da177e4 | 288 | |
2263576c LM |
289 | /* Just keep going */ |
290 | break; | |
1da177e4 | 291 | |
2263576c | 292 | case AE_CTRL_TERMINATE: |
1da177e4 | 293 | |
2263576c | 294 | /* Exit now, with OK status */ |
1da177e4 | 295 | |
2263576c | 296 | return_ACPI_STATUS(AE_OK); |
1da177e4 | 297 | |
2263576c | 298 | default: |
1da177e4 | 299 | |
2263576c | 300 | /* All others are valid exceptions */ |
1da177e4 | 301 | |
2263576c LM |
302 | return_ACPI_STATUS(status); |
303 | } | |
304 | } | |
305 | ||
306 | /* | |
307 | * Depth first search: Attempt to go down another level in the | |
73a3090a | 308 | * namespace if we are allowed to. Don't go any further if we have |
2263576c LM |
309 | * reached the caller specified maximum depth or if the user |
310 | * function has specified that the maximum depth has been reached. | |
311 | */ | |
312 | if (!node_previously_visited && | |
313 | (level < max_depth) && (status != AE_CTRL_DEPTH)) { | |
314 | if (child_node->child) { | |
315 | ||
316 | /* There is at least one child of this node, visit it */ | |
317 | ||
318 | level++; | |
319 | parent_node = child_node; | |
320 | child_node = | |
321 | acpi_ns_get_next_node(parent_node, NULL); | |
322 | continue; | |
1da177e4 | 323 | } |
2263576c | 324 | } |
1da177e4 | 325 | |
2263576c | 326 | /* No more children, re-visit this node */ |
3effba32 | 327 | |
2263576c LM |
328 | if (!node_previously_visited) { |
329 | node_previously_visited = TRUE; | |
330 | continue; | |
331 | } | |
3effba32 | 332 | |
2263576c LM |
333 | /* No more children, visit peers */ |
334 | ||
335 | child_node = acpi_ns_get_next_node(parent_node, child_node); | |
336 | if (child_node) { | |
337 | node_previously_visited = FALSE; | |
338 | } | |
339 | ||
340 | /* No peers, re-visit parent */ | |
341 | ||
342 | else { | |
1da177e4 | 343 | /* |
3effba32 BM |
344 | * No more children of this node (acpi_ns_get_next_node failed), go |
345 | * back upwards in the namespace tree to the node's parent. | |
1da177e4 LT |
346 | */ |
347 | level--; | |
348 | child_node = parent_node; | |
c45b5c09 | 349 | parent_node = parent_node->parent; |
2263576c LM |
350 | |
351 | node_previously_visited = TRUE; | |
1da177e4 LT |
352 | } |
353 | } | |
354 | ||
355 | /* Complete walk, not terminated by user function */ | |
356 | ||
4be44fcd | 357 | return_ACPI_STATUS(AE_OK); |
1da177e4 | 358 | } |