diff options
Diffstat (limited to 'drivers/acpi/acpica/nssearch.c')
| -rw-r--r-- | drivers/acpi/acpica/nssearch.c | 415 |
1 files changed, 415 insertions, 0 deletions
diff --git a/drivers/acpi/acpica/nssearch.c b/drivers/acpi/acpica/nssearch.c new file mode 100644 index 00000000000..a76c731e3ba --- /dev/null +++ b/drivers/acpi/acpica/nssearch.c @@ -0,0 +1,415 @@ +/******************************************************************************* + * + * Module Name: nssearch - Namespace search + * + ******************************************************************************/ + +/* + * Copyright (C) 2000 - 2008, Intel Corp. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions, and the following disclaimer, + * without modification. + * 2. Redistributions in binary form must reproduce at minimum a disclaimer + * substantially similar to the "NO WARRANTY" disclaimer below + * ("Disclaimer") and any redistribution must be conditioned upon + * including a substantially similar Disclaimer requirement for further + * binary redistribution. + * 3. Neither the names of the above-listed copyright holders nor the names + * of any contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * Alternatively, this software may be distributed under the terms of the + * GNU General Public License ("GPL") version 2 as published by the Free + * Software Foundation. + * + * NO WARRANTY + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, + * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING + * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGES. + */ + +#include <acpi/acpi.h> +#include <acpi/accommon.h> +#include <acpi/acnamesp.h> + +#define _COMPONENT ACPI_NAMESPACE +ACPI_MODULE_NAME("nssearch") + +/* Local prototypes */ +static acpi_status +acpi_ns_search_parent_tree(u32 target_name, + struct acpi_namespace_node *node, + acpi_object_type type, + struct acpi_namespace_node **return_node); + +/******************************************************************************* + * + * FUNCTION: acpi_ns_search_one_scope + * + * PARAMETERS: target_name - Ascii ACPI name to search for + * parent_node - Starting node where search will begin + * Type - Object type to match + * return_node - Where the matched Named obj is returned + * + * RETURN: Status + * + * DESCRIPTION: Search a single level of the namespace. Performs a + * simple search of the specified level, and does not add + * entries or search parents. + * + * + * Named object lists are built (and subsequently dumped) in the + * order in which the names are encountered during the namespace load; + * + * All namespace searching is linear in this implementation, but + * could be easily modified to support any improved search + * algorithm. However, the linear search was chosen for simplicity + * and because the trees are small and the other interpreter + * execution overhead is relatively high. + * + * Note: CPU execution analysis has shown that the AML interpreter spends + * a very small percentage of its time searching the namespace. Therefore, + * the linear search seems to be sufficient, as there would seem to be + * little value in improving the search. + * + ******************************************************************************/ + +acpi_status +acpi_ns_search_one_scope(u32 target_name, + struct acpi_namespace_node *parent_node, + acpi_object_type type, + struct acpi_namespace_node **return_node) +{ + struct acpi_namespace_node *node; + + ACPI_FUNCTION_TRACE(ns_search_one_scope); + +#ifdef ACPI_DEBUG_OUTPUT + if (ACPI_LV_NAMES & acpi_dbg_level) { + char *scope_name; + + scope_name = acpi_ns_get_external_pathname(parent_node); + if (scope_name) { + ACPI_DEBUG_PRINT((ACPI_DB_NAMES, + "Searching %s (%p) For [%4.4s] (%s)\n", + scope_name, parent_node, + ACPI_CAST_PTR(char, &target_name), + acpi_ut_get_type_name(type))); + + ACPI_FREE(scope_name); + } + } +#endif + + /* + * Search for name at this namespace level, which is to say that we + * must search for the name among the children of this object + */ + node = parent_node->child; + while (node) { + + /* Check for match against the name */ + + if (node->name.integer == target_name) { + + /* Resolve a control method alias if any */ + + if (acpi_ns_get_type(node) == + ACPI_TYPE_LOCAL_METHOD_ALIAS) { + node = + ACPI_CAST_PTR(struct acpi_namespace_node, + node->object); + } + + /* Found matching entry */ + + ACPI_DEBUG_PRINT((ACPI_DB_NAMES, + "Name [%4.4s] (%s) %p found in scope [%4.4s] %p\n", + ACPI_CAST_PTR(char, &target_name), + acpi_ut_get_type_name(node->type), + node, + acpi_ut_get_node_name(parent_node), + parent_node)); + + *return_node = node; + return_ACPI_STATUS(AE_OK); + } + + /* + * The last entry in the list points back to the parent, + * so a flag is used to indicate the end-of-list + */ + if (node->flags & ANOBJ_END_OF_PEER_LIST) { + + /* Searched entire list, we are done */ + + break; + } + + /* Didn't match name, move on to the next peer object */ + + node = node->peer; + } + + /* Searched entire namespace level, not found */ + + ACPI_DEBUG_PRINT((ACPI_DB_NAMES, + "Name [%4.4s] (%s) not found in search in scope [%4.4s] %p first child %p\n", + ACPI_CAST_PTR(char, &target_name), + acpi_ut_get_type_name(type), + acpi_ut_get_node_name(parent_node), parent_node, + parent_node->child)); + + return_ACPI_STATUS(AE_NOT_FOUND); +} + +/******************************************************************************* + * + * FUNCTION: acpi_ns_search_parent_tree + * + * PARAMETERS: target_name - Ascii ACPI name to search for + * Node - Starting node where search will begin + * Type - Object type to match + * return_node - Where the matched Node is returned + * + * RETURN: Status + * + * DESCRIPTION: Called when a name has not been found in the current namespace + * level. Before adding it or giving up, ACPI scope rules require + * searching enclosing scopes in cases identified by acpi_ns_local(). + * + * "A name is located by finding the matching name in the current + * name space, and then in the parent name space. If the parent + * name space does not contain the name, the search continues + * recursively until either the name is found or the name space + * does not have a parent (the root of the name space). This + * indicates that the name is not found" (From ACPI Specification, + * section 5.3) + * + ******************************************************************************/ + +static acpi_status +acpi_ns_search_parent_tree(u32 target_name, + struct acpi_namespace_node *node, + acpi_object_type type, + struct acpi_namespace_node **return_node) +{ + acpi_status status; + struct acpi_namespace_node *parent_node; + + ACPI_FUNCTION_TRACE(ns_search_parent_tree); + + parent_node = acpi_ns_get_parent_node(node); + + /* + * If there is no parent (i.e., we are at the root) or type is "local", + * we won't be searching the parent tree. + */ + if (!parent_node) { + ACPI_DEBUG_PRINT((ACPI_DB_NAMES, "[%4.4s] has no parent\n", + ACPI_CAST_PTR(char, &target_name))); + return_ACPI_STATUS(AE_NOT_FOUND); + } + + if (acpi_ns_local(type)) { + ACPI_DEBUG_PRINT((ACPI_DB_NAMES, + "[%4.4s] type [%s] must be local to this scope (no parent search)\n", + ACPI_CAST_PTR(char, &target_name), + acpi_ut_get_type_name(type))); + return_ACPI_STATUS(AE_NOT_FOUND); + } + + /* Search the parent tree */ + + ACPI_DEBUG_PRINT((ACPI_DB_NAMES, + "Searching parent [%4.4s] for [%4.4s]\n", + acpi_ut_get_node_name(parent_node), + ACPI_CAST_PTR(char, &target_name))); + + /* + * Search parents until target is found or we have backed up to the root + */ + while (parent_node) { + /* + * Search parent scope. Use TYPE_ANY because we don't care about the + * object type at this point, we only care about the existence of + * the actual name we are searching for. Typechecking comes later. + */ + status = + acpi_ns_search_one_scope(target_name, parent_node, + ACPI_TYPE_ANY, return_node); + if (ACPI_SUCCESS(status)) { + return_ACPI_STATUS(status); + } + + /* Not found here, go up another level (until we reach the root) */ + + parent_node = acpi_ns_get_parent_node(parent_node); + } + + /* Not found in parent tree */ + + return_ACPI_STATUS(AE_NOT_FOUND); +} + +/******************************************************************************* + * + * FUNCTION: acpi_ns_search_and_enter + * + * PARAMETERS: target_name - Ascii ACPI name to search for (4 chars) + * walk_state - Current state of the walk + * Node - Starting node where search will begin + * interpreter_mode - Add names only in ACPI_MODE_LOAD_PASS_x. + * Otherwise,search only. + * Type - Object type to match + * Flags - Flags describing the search restrictions + * return_node - Where the Node is returned + * + * RETURN: Status + * + * DESCRIPTION: Search for a name segment in a single namespace level, + * optionally adding it if it is not found. If the passed + * Type is not Any and the type previously stored in the + * entry was Any (i.e. unknown), update the stored type. + * + * In ACPI_IMODE_EXECUTE, search only. + * In other modes, search and add if not found. + * + ******************************************************************************/ + +acpi_status +acpi_ns_search_and_enter(u32 target_name, + struct acpi_walk_state *walk_state, + struct acpi_namespace_node *node, + acpi_interpreter_mode interpreter_mode, + acpi_object_type type, + u32 flags, struct acpi_namespace_node **return_node) +{ + acpi_status status; + struct acpi_namespace_node *new_node; + + ACPI_FUNCTION_TRACE(ns_search_and_enter); + + /* Parameter validation */ + + if (!node || !target_name || !return_node) { + ACPI_ERROR((AE_INFO, + "Null parameter: Node %p Name %X ReturnNode %p", + node, target_name, return_node)); + return_ACPI_STATUS(AE_BAD_PARAMETER); + } + + /* + * Name must consist of valid ACPI characters. We will repair the name if + * necessary because we don't want to abort because of this, but we want + * all namespace names to be printable. A warning message is appropriate. + * + * This issue came up because there are in fact machines that exhibit + * this problem, and we want to be able to enable ACPI support for them, + * even though there are a few bad names. + */ + if (!acpi_ut_valid_acpi_name(target_name)) { + target_name = + acpi_ut_repair_name(ACPI_CAST_PTR(char, &target_name)); + + /* Report warning only if in strict mode or debug mode */ + + if (!acpi_gbl_enable_interpreter_slack) { + ACPI_WARNING((AE_INFO, + "Found bad character(s) in name, repaired: [%4.4s]\n", + ACPI_CAST_PTR(char, &target_name))); + } else { + ACPI_DEBUG_PRINT((ACPI_DB_INFO, + "Found bad character(s) in name, repaired: [%4.4s]\n", + ACPI_CAST_PTR(char, &target_name))); + } + } + + /* Try to find the name in the namespace level specified by the caller */ + + *return_node = ACPI_ENTRY_NOT_FOUND; + status = acpi_ns_search_one_scope(target_name, node, type, return_node); + if (status != AE_NOT_FOUND) { + /* + * If we found it AND the request specifies that a find is an error, + * return the error + */ + if ((status == AE_OK) && (flags & ACPI_NS_ERROR_IF_FOUND)) { + status = AE_ALREADY_EXISTS; + } + + /* Either found it or there was an error: finished either way */ + + return_ACPI_STATUS(status); + } + + /* + * The name was not found. If we are NOT performing the first pass + * (name entry) of loading the namespace, search the parent tree (all the + * way to the root if necessary.) We don't want to perform the parent + * search when the namespace is actually being loaded. We want to perform + * the search when namespace references are being resolved (load pass 2) + * and during the execution phase. + */ + if ((interpreter_mode != ACPI_IMODE_LOAD_PASS1) && + (flags & ACPI_NS_SEARCH_PARENT)) { + /* + * Not found at this level - search parent tree according to the + * ACPI specification + */ + status = + acpi_ns_search_parent_tree(target_name, node, type, + return_node); + if (ACPI_SUCCESS(status)) { + return_ACPI_STATUS(status); + } + } + + /* In execute mode, just search, never add names. Exit now */ + + if (interpreter_mode == ACPI_IMODE_EXECUTE) { + ACPI_DEBUG_PRINT((ACPI_DB_NAMES, + "%4.4s Not found in %p [Not adding]\n", + ACPI_CAST_PTR(char, &target_name), node)); + + return_ACPI_STATUS(AE_NOT_FOUND); + } + + /* Create the new named object */ + + new_node = acpi_ns_create_node(target_name); + if (!new_node) { + return_ACPI_STATUS(AE_NO_MEMORY); + } +#ifdef ACPI_ASL_COMPILER + /* + * Node is an object defined by an External() statement + */ + if (flags & ACPI_NS_EXTERNAL) { + new_node->flags |= ANOBJ_IS_EXTERNAL; + } +#endif + + if (flags & ACPI_NS_TEMPORARY) { + new_node->flags |= ANOBJ_TEMPORARY; + } + + /* Install the new object into the parent's list of children */ + + acpi_ns_install_node(walk_state, node, new_node, type); + *return_node = new_node; + return_ACPI_STATUS(AE_OK); +} |