ia64/linux-2.6.18-xen.hg

view drivers/acpi/namespace/nsaccess.c @ 912:dd42cdb0ab89

[IA64] Build blktap2 driver by default in x86 builds.

add CONFIG_XEN_BLKDEV_TAP2=y to buildconfigs/linux-defconfig_xen_ia64.

Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
author Isaku Yamahata <yamahata@valinux.co.jp>
date Mon Jun 29 12:09:16 2009 +0900 (2009-06-29)
parents 831230e53067
children
line source
1 /*******************************************************************************
2 *
3 * Module Name: nsaccess - Top-level functions for accessing ACPI namespace
4 *
5 ******************************************************************************/
7 /*
8 * Copyright (C) 2000 - 2006, 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 */
44 #include <acpi/acpi.h>
45 #include <acpi/amlcode.h>
46 #include <acpi/acnamesp.h>
47 #include <acpi/acdispat.h>
49 #define _COMPONENT ACPI_NAMESPACE
50 ACPI_MODULE_NAME("nsaccess")
52 /*******************************************************************************
53 *
54 * FUNCTION: acpi_ns_root_initialize
55 *
56 * PARAMETERS: None
57 *
58 * RETURN: Status
59 *
60 * DESCRIPTION: Allocate and initialize the default root named objects
61 *
62 * MUTEX: Locks namespace for entire execution
63 *
64 ******************************************************************************/
65 acpi_status acpi_ns_root_initialize(void)
66 {
67 acpi_status status;
68 const struct acpi_predefined_names *init_val = NULL;
69 struct acpi_namespace_node *new_node;
70 union acpi_operand_object *obj_desc;
71 acpi_string val = NULL;
73 ACPI_FUNCTION_TRACE(ns_root_initialize);
75 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
76 if (ACPI_FAILURE(status)) {
77 return_ACPI_STATUS(status);
78 }
80 /*
81 * The global root ptr is initially NULL, so a non-NULL value indicates
82 * that acpi_ns_root_initialize() has already been called; just return.
83 */
84 if (acpi_gbl_root_node) {
85 status = AE_OK;
86 goto unlock_and_exit;
87 }
89 /*
90 * Tell the rest of the subsystem that the root is initialized
91 * (This is OK because the namespace is locked)
92 */
93 acpi_gbl_root_node = &acpi_gbl_root_node_struct;
95 /* Enter the pre-defined names in the name table */
97 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
98 "Entering predefined entries into namespace\n"));
100 for (init_val = acpi_gbl_pre_defined_names; init_val->name; init_val++) {
102 /* _OSI is optional for now, will be permanent later */
104 if (!ACPI_STRCMP(init_val->name, "_OSI")
105 && !acpi_gbl_create_osi_method) {
106 continue;
107 }
109 status = acpi_ns_lookup(NULL, init_val->name, init_val->type,
110 ACPI_IMODE_LOAD_PASS2,
111 ACPI_NS_NO_UPSEARCH, NULL, &new_node);
113 if (ACPI_FAILURE(status) || (!new_node)) { /* Must be on same line for code converter */
114 ACPI_EXCEPTION((AE_INFO, status,
115 "Could not create predefined name %s",
116 init_val->name));
117 }
119 /*
120 * Name entered successfully.
121 * If entry in pre_defined_names[] specifies an
122 * initial value, create the initial value.
123 */
124 if (init_val->val) {
125 status = acpi_os_predefined_override(init_val, &val);
126 if (ACPI_FAILURE(status)) {
127 ACPI_ERROR((AE_INFO,
128 "Could not override predefined %s",
129 init_val->name));
130 }
132 if (!val) {
133 val = init_val->val;
134 }
136 /*
137 * Entry requests an initial value, allocate a
138 * descriptor for it.
139 */
140 obj_desc =
141 acpi_ut_create_internal_object(init_val->type);
142 if (!obj_desc) {
143 status = AE_NO_MEMORY;
144 goto unlock_and_exit;
145 }
147 /*
148 * Convert value string from table entry to
149 * internal representation. Only types actually
150 * used for initial values are implemented here.
151 */
152 switch (init_val->type) {
153 case ACPI_TYPE_METHOD:
154 obj_desc->method.param_count =
155 (u8) ACPI_TO_INTEGER(val);
156 obj_desc->common.flags |= AOPOBJ_DATA_VALID;
158 #if defined (ACPI_ASL_COMPILER)
160 /* Save the parameter count for the i_aSL compiler */
162 new_node->value = obj_desc->method.param_count;
163 #else
164 /* Mark this as a very SPECIAL method */
166 obj_desc->method.method_flags =
167 AML_METHOD_INTERNAL_ONLY;
169 #ifndef ACPI_DUMP_APP
170 obj_desc->method.implementation =
171 acpi_ut_osi_implementation;
172 #endif
173 #endif
174 break;
176 case ACPI_TYPE_INTEGER:
178 obj_desc->integer.value = ACPI_TO_INTEGER(val);
179 break;
181 case ACPI_TYPE_STRING:
183 /*
184 * Build an object around the static string
185 */
186 obj_desc->string.length =
187 (u32) ACPI_STRLEN(val);
188 obj_desc->string.pointer = val;
189 obj_desc->common.flags |= AOPOBJ_STATIC_POINTER;
190 break;
192 case ACPI_TYPE_MUTEX:
194 obj_desc->mutex.node = new_node;
195 obj_desc->mutex.sync_level =
196 (u8) (ACPI_TO_INTEGER(val) - 1);
198 if (ACPI_STRCMP(init_val->name, "_GL_") == 0) {
200 /* Create a counting semaphore for the global lock */
202 status =
203 acpi_os_create_semaphore
204 (ACPI_NO_UNIT_LIMIT, 1,
205 &acpi_gbl_global_lock_semaphore);
206 if (ACPI_FAILURE(status)) {
207 acpi_ut_remove_reference
208 (obj_desc);
209 goto unlock_and_exit;
210 }
212 /* Mark this mutex as very special */
214 obj_desc->mutex.os_mutex =
215 ACPI_GLOBAL_LOCK;
216 } else {
217 /* Create a mutex */
219 status =
220 acpi_os_create_mutex(&obj_desc->
221 mutex.
222 os_mutex);
223 if (ACPI_FAILURE(status)) {
224 acpi_ut_remove_reference
225 (obj_desc);
226 goto unlock_and_exit;
227 }
228 }
229 break;
231 default:
233 ACPI_ERROR((AE_INFO,
234 "Unsupported initial type value %X",
235 init_val->type));
236 acpi_ut_remove_reference(obj_desc);
237 obj_desc = NULL;
238 continue;
239 }
241 /* Store pointer to value descriptor in the Node */
243 status = acpi_ns_attach_object(new_node, obj_desc,
244 ACPI_GET_OBJECT_TYPE
245 (obj_desc));
247 /* Remove local reference to the object */
249 acpi_ut_remove_reference(obj_desc);
250 }
251 }
253 unlock_and_exit:
254 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
256 /* Save a handle to "_GPE", it is always present */
258 if (ACPI_SUCCESS(status)) {
259 status = acpi_ns_get_node(NULL, "\\_GPE", ACPI_NS_NO_UPSEARCH,
260 &acpi_gbl_fadt_gpe_device);
261 }
263 return_ACPI_STATUS(status);
264 }
266 /*******************************************************************************
267 *
268 * FUNCTION: acpi_ns_lookup
269 *
270 * PARAMETERS: scope_info - Current scope info block
271 * Pathname - Search pathname, in internal format
272 * (as represented in the AML stream)
273 * Type - Type associated with name
274 * interpreter_mode - IMODE_LOAD_PASS2 => add name if not found
275 * Flags - Flags describing the search restrictions
276 * walk_state - Current state of the walk
277 * return_node - Where the Node is placed (if found
278 * or created successfully)
279 *
280 * RETURN: Status
281 *
282 * DESCRIPTION: Find or enter the passed name in the name space.
283 * Log an error if name not found in Exec mode.
284 *
285 * MUTEX: Assumes namespace is locked.
286 *
287 ******************************************************************************/
289 acpi_status
290 acpi_ns_lookup(union acpi_generic_state *scope_info,
291 char *pathname,
292 acpi_object_type type,
293 acpi_interpreter_mode interpreter_mode,
294 u32 flags,
295 struct acpi_walk_state *walk_state,
296 struct acpi_namespace_node **return_node)
297 {
298 acpi_status status;
299 char *path = pathname;
300 struct acpi_namespace_node *prefix_node;
301 struct acpi_namespace_node *current_node = NULL;
302 struct acpi_namespace_node *this_node = NULL;
303 u32 num_segments;
304 u32 num_carats;
305 acpi_name simple_name;
306 acpi_object_type type_to_check_for;
307 acpi_object_type this_search_type;
308 u32 search_parent_flag = ACPI_NS_SEARCH_PARENT;
309 u32 local_flags;
311 ACPI_FUNCTION_TRACE(ns_lookup);
313 if (!return_node) {
314 return_ACPI_STATUS(AE_BAD_PARAMETER);
315 }
317 local_flags = flags & ~(ACPI_NS_ERROR_IF_FOUND | ACPI_NS_SEARCH_PARENT);
318 *return_node = ACPI_ENTRY_NOT_FOUND;
319 acpi_gbl_ns_lookup_count++;
321 if (!acpi_gbl_root_node) {
322 return_ACPI_STATUS(AE_NO_NAMESPACE);
323 }
325 /*
326 * Get the prefix scope.
327 * A null scope means use the root scope
328 */
329 if ((!scope_info) || (!scope_info->scope.node)) {
330 ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
331 "Null scope prefix, using root node (%p)\n",
332 acpi_gbl_root_node));
334 prefix_node = acpi_gbl_root_node;
335 } else {
336 prefix_node = scope_info->scope.node;
337 if (ACPI_GET_DESCRIPTOR_TYPE(prefix_node) !=
338 ACPI_DESC_TYPE_NAMED) {
339 ACPI_ERROR((AE_INFO, "%p is not a namespace node [%s]",
340 prefix_node,
341 acpi_ut_get_descriptor_name(prefix_node)));
342 return_ACPI_STATUS(AE_AML_INTERNAL);
343 }
345 if (!(flags & ACPI_NS_PREFIX_IS_SCOPE)) {
346 /*
347 * This node might not be a actual "scope" node (such as a
348 * Device/Method, etc.) It could be a Package or other object node.
349 * Backup up the tree to find the containing scope node.
350 */
351 while (!acpi_ns_opens_scope(prefix_node->type) &&
352 prefix_node->type != ACPI_TYPE_ANY) {
353 prefix_node =
354 acpi_ns_get_parent_node(prefix_node);
355 }
356 }
357 }
359 /* Save type TBD: may be no longer necessary */
361 type_to_check_for = type;
363 /*
364 * Begin examination of the actual pathname
365 */
366 if (!pathname) {
368 /* A Null name_path is allowed and refers to the root */
370 num_segments = 0;
371 this_node = acpi_gbl_root_node;
372 path = "";
374 ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
375 "Null Pathname (Zero segments), Flags=%X\n",
376 flags));
377 } else {
378 /*
379 * Name pointer is valid (and must be in internal name format)
380 *
381 * Check for scope prefixes:
382 *
383 * As represented in the AML stream, a namepath consists of an
384 * optional scope prefix followed by a name segment part.
385 *
386 * If present, the scope prefix is either a Root Prefix (in
387 * which case the name is fully qualified), or one or more
388 * Parent Prefixes (in which case the name's scope is relative
389 * to the current scope).
390 */
391 if (*path == (u8) AML_ROOT_PREFIX) {
393 /* Pathname is fully qualified, start from the root */
395 this_node = acpi_gbl_root_node;
396 search_parent_flag = ACPI_NS_NO_UPSEARCH;
398 /* Point to name segment part */
400 path++;
402 ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
403 "Path is absolute from root [%p]\n",
404 this_node));
405 } else {
406 /* Pathname is relative to current scope, start there */
408 ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
409 "Searching relative to prefix scope [%4.4s] (%p)\n",
410 acpi_ut_get_node_name(prefix_node),
411 prefix_node));
413 /*
414 * Handle multiple Parent Prefixes (carat) by just getting
415 * the parent node for each prefix instance.
416 */
417 this_node = prefix_node;
418 num_carats = 0;
419 while (*path == (u8) AML_PARENT_PREFIX) {
421 /* Name is fully qualified, no search rules apply */
423 search_parent_flag = ACPI_NS_NO_UPSEARCH;
424 /*
425 * Point past this prefix to the name segment
426 * part or the next Parent Prefix
427 */
428 path++;
430 /* Backup to the parent node */
432 num_carats++;
433 this_node = acpi_ns_get_parent_node(this_node);
434 if (!this_node) {
436 /* Current scope has no parent scope */
438 ACPI_ERROR((AE_INFO,
439 "ACPI path has too many parent prefixes (^) - reached beyond root node"));
440 return_ACPI_STATUS(AE_NOT_FOUND);
441 }
442 }
444 if (search_parent_flag == ACPI_NS_NO_UPSEARCH) {
445 ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
446 "Search scope is [%4.4s], path has %d carat(s)\n",
447 acpi_ut_get_node_name
448 (this_node), num_carats));
449 }
450 }
452 /*
453 * Determine the number of ACPI name segments in this pathname.
454 *
455 * The segment part consists of either:
456 * - A Null name segment (0)
457 * - A dual_name_prefix followed by two 4-byte name segments
458 * - A multi_name_prefix followed by a byte indicating the
459 * number of segments and the segments themselves.
460 * - A single 4-byte name segment
461 *
462 * Examine the name prefix opcode, if any, to determine the number of
463 * segments.
464 */
465 switch (*path) {
466 case 0:
467 /*
468 * Null name after a root or parent prefixes. We already
469 * have the correct target node and there are no name segments.
470 */
471 num_segments = 0;
472 type = this_node->type;
474 ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
475 "Prefix-only Pathname (Zero name segments), Flags=%X\n",
476 flags));
477 break;
479 case AML_DUAL_NAME_PREFIX:
481 /* More than one name_seg, search rules do not apply */
483 search_parent_flag = ACPI_NS_NO_UPSEARCH;
485 /* Two segments, point to first name segment */
487 num_segments = 2;
488 path++;
490 ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
491 "Dual Pathname (2 segments, Flags=%X)\n",
492 flags));
493 break;
495 case AML_MULTI_NAME_PREFIX_OP:
497 /* More than one name_seg, search rules do not apply */
499 search_parent_flag = ACPI_NS_NO_UPSEARCH;
501 /* Extract segment count, point to first name segment */
503 path++;
504 num_segments = (u32) (u8) * path;
505 path++;
507 ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
508 "Multi Pathname (%d Segments, Flags=%X)\n",
509 num_segments, flags));
510 break;
512 default:
513 /*
514 * Not a Null name, no Dual or Multi prefix, hence there is
515 * only one name segment and Pathname is already pointing to it.
516 */
517 num_segments = 1;
519 ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
520 "Simple Pathname (1 segment, Flags=%X)\n",
521 flags));
522 break;
523 }
525 ACPI_DEBUG_EXEC(acpi_ns_print_pathname(num_segments, path));
526 }
528 /*
529 * Search namespace for each segment of the name. Loop through and
530 * verify (or add to the namespace) each name segment.
531 *
532 * The object type is significant only at the last name
533 * segment. (We don't care about the types along the path, only
534 * the type of the final target object.)
535 */
536 this_search_type = ACPI_TYPE_ANY;
537 current_node = this_node;
538 while (num_segments && current_node) {
539 num_segments--;
540 if (!num_segments) {
541 /*
542 * This is the last segment, enable typechecking
543 */
544 this_search_type = type;
546 /*
547 * Only allow automatic parent search (search rules) if the caller
548 * requested it AND we have a single, non-fully-qualified name_seg
549 */
550 if ((search_parent_flag != ACPI_NS_NO_UPSEARCH) &&
551 (flags & ACPI_NS_SEARCH_PARENT)) {
552 local_flags |= ACPI_NS_SEARCH_PARENT;
553 }
555 /* Set error flag according to caller */
557 if (flags & ACPI_NS_ERROR_IF_FOUND) {
558 local_flags |= ACPI_NS_ERROR_IF_FOUND;
559 }
560 }
562 /* Extract one ACPI name from the front of the pathname */
564 ACPI_MOVE_32_TO_32(&simple_name, path);
566 /* Try to find the single (4 character) ACPI name */
568 status =
569 acpi_ns_search_and_enter(simple_name, walk_state,
570 current_node, interpreter_mode,
571 this_search_type, local_flags,
572 &this_node);
573 if (ACPI_FAILURE(status)) {
574 if (status == AE_NOT_FOUND) {
576 /* Name not found in ACPI namespace */
578 ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
579 "Name [%4.4s] not found in scope [%4.4s] %p\n",
580 (char *)&simple_name,
581 (char *)&current_node->name,
582 current_node));
583 }
585 *return_node = this_node;
586 return_ACPI_STATUS(status);
587 }
589 /*
590 * Sanity typecheck of the target object:
591 *
592 * If 1) This is the last segment (num_segments == 0)
593 * 2) And we are looking for a specific type
594 * (Not checking for TYPE_ANY)
595 * 3) Which is not an alias
596 * 4) Which is not a local type (TYPE_SCOPE)
597 * 5) And the type of target object is known (not TYPE_ANY)
598 * 6) And target object does not match what we are looking for
599 *
600 * Then we have a type mismatch. Just warn and ignore it.
601 */
602 if ((num_segments == 0) &&
603 (type_to_check_for != ACPI_TYPE_ANY) &&
604 (type_to_check_for != ACPI_TYPE_LOCAL_ALIAS) &&
605 (type_to_check_for != ACPI_TYPE_LOCAL_METHOD_ALIAS) &&
606 (type_to_check_for != ACPI_TYPE_LOCAL_SCOPE) &&
607 (this_node->type != ACPI_TYPE_ANY) &&
608 (this_node->type != type_to_check_for)) {
610 /* Complain about a type mismatch */
612 ACPI_WARNING((AE_INFO,
613 "NsLookup: Type mismatch on %4.4s (%s), searching for (%s)",
614 ACPI_CAST_PTR(char, &simple_name),
615 acpi_ut_get_type_name(this_node->type),
616 acpi_ut_get_type_name
617 (type_to_check_for)));
618 }
620 /*
621 * If this is the last name segment and we are not looking for a
622 * specific type, but the type of found object is known, use that type
623 * to see if it opens a scope.
624 */
625 if ((num_segments == 0) && (type == ACPI_TYPE_ANY)) {
626 type = this_node->type;
627 }
629 /* Point to next name segment and make this node current */
631 path += ACPI_NAME_SIZE;
632 current_node = this_node;
633 }
635 /*
636 * Always check if we need to open a new scope
637 */
638 if (!(flags & ACPI_NS_DONT_OPEN_SCOPE) && (walk_state)) {
639 /*
640 * If entry is a type which opens a scope, push the new scope on the
641 * scope stack.
642 */
643 if (acpi_ns_opens_scope(type)) {
644 status =
645 acpi_ds_scope_stack_push(this_node, type,
646 walk_state);
647 if (ACPI_FAILURE(status)) {
648 return_ACPI_STATUS(status);
649 }
650 }
651 }
653 *return_node = this_node;
654 return_ACPI_STATUS(AE_OK);
655 }