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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /drivers/acpi/acpica/nssearch.c
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/acpi/acpica/nssearch.c')
-rw-r--r--drivers/acpi/acpica/nssearch.c396
1 files changed, 396 insertions, 0 deletions
diff --git a/drivers/acpi/acpica/nssearch.c b/drivers/acpi/acpica/nssearch.c
new file mode 100644
index 000000000..f594ab75a
--- /dev/null
+++ b/drivers/acpi/acpica/nssearch.c
@@ -0,0 +1,396 @@
+// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
+/*******************************************************************************
+ *
+ * Module Name: nssearch - Namespace search
+ *
+ ******************************************************************************/
+
+#include <acpi/acpi.h>
+#include "accommon.h"
+#include "acnamesp.h"
+
+#ifdef ACPI_ASL_COMPILER
+#include "amlcode.h"
+#endif
+
+#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_normalized_pathname(parent_node, TRUE);
+ 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);
+ }
+
+ /* 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 = node->parent;
+
+ /*
+ * 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 = parent_node->parent;
+ }
+
+ /* 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 0x%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.
+ */
+ acpi_ut_repair_name(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) {
+
+ /* The node was found in the namespace */
+
+ /*
+ * If the namespace override feature is enabled for this node,
+ * delete any existing attached sub-object and make the node
+ * look like a new node that is owned by the override table.
+ */
+ if (flags & ACPI_NS_OVERRIDE_IF_FOUND) {
+ ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
+ "Namespace override: %4.4s pass %u type %X Owner %X\n",
+ ACPI_CAST_PTR(char,
+ &target_name),
+ interpreter_mode,
+ (*return_node)->type,
+ walk_state->owner_id));
+
+ acpi_ns_delete_children(*return_node);
+ if (acpi_gbl_runtime_namespace_override) {
+ acpi_ut_remove_reference((*return_node)->object);
+ (*return_node)->object = NULL;
+ (*return_node)->owner_id =
+ walk_state->owner_id;
+ } else {
+ acpi_ns_remove_node(*return_node);
+ *return_node = ACPI_ENTRY_NOT_FOUND;
+ }
+ }
+
+ /* Return an error if we don't expect to find the object */
+
+ else if (flags & ACPI_NS_ERROR_IF_FOUND) {
+ status = AE_ALREADY_EXISTS;
+ }
+ }
+#ifdef ACPI_ASL_COMPILER
+ if (*return_node && (*return_node)->type == ACPI_TYPE_ANY) {
+ (*return_node)->flags |= ANOBJ_IS_EXTERNAL;
+ }
+#endif
+
+ /* 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 ||
+ (walk_state && walk_state->opcode == AML_SCOPE_OP)) {
+ 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);
+}