--- /dev/null
+/******************************************************************************
+ *
+ * Module Name: utcache - local cache allocation routines
+ *
+ *****************************************************************************/
+
+/*
+ * Copyright (C) 2000 - 2006, R. Byron Moore
+ * 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>
+
+#define _COMPONENT ACPI_UTILITIES
+ACPI_MODULE_NAME("utcache")
+
+#ifdef ACPI_USE_LOCAL_CACHE
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_os_create_cache
+ *
+ * PARAMETERS: cache_name - Ascii name for the cache
+ * object_size - Size of each cached object
+ * max_depth - Maximum depth of the cache (in objects)
+ * return_cache - Where the new cache object is returned
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Create a cache object
+ *
+ ******************************************************************************/
+acpi_status
+acpi_os_create_cache(char *cache_name,
+ u16 object_size,
+ u16 max_depth, struct acpi_memory_list **return_cache)
+{
+ struct acpi_memory_list *cache;
+
+ ACPI_FUNCTION_ENTRY();
+
+ if (!cache_name || !return_cache || (object_size < 16)) {
+ return (AE_BAD_PARAMETER);
+ }
+
+ /* Create the cache object */
+
+ cache = acpi_os_allocate(sizeof(struct acpi_memory_list));
+ if (!cache) {
+ return (AE_NO_MEMORY);
+ }
+
+ /* Populate the cache object and return it */
+
+ ACPI_MEMSET(cache, 0, sizeof(struct acpi_memory_list));
+ cache->link_offset = 8;
+ cache->list_name = cache_name;
+ cache->object_size = object_size;
+ cache->max_depth = max_depth;
+
+ *return_cache = cache;
+ return (AE_OK);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_os_purge_cache
+ *
+ * PARAMETERS: Cache - Handle to cache object
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Free all objects within the requested cache.
+ *
+ ******************************************************************************/
+
+acpi_status acpi_os_purge_cache(struct acpi_memory_list * cache)
+{
+ char *next;
+
+ ACPI_FUNCTION_ENTRY();
+
+ if (!cache) {
+ return (AE_BAD_PARAMETER);
+ }
+
+ /* Walk the list of objects in this cache */
+
+ while (cache->list_head) {
+ /* Delete and unlink one cached state object */
+
+ next = *(ACPI_CAST_INDIRECT_PTR(char,
+ &(((char *)cache->
+ list_head)[cache->
+ link_offset])));
+ ACPI_MEM_FREE(cache->list_head);
+
+ cache->list_head = next;
+ cache->current_depth--;
+ }
+
+ return (AE_OK);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_os_delete_cache
+ *
+ * PARAMETERS: Cache - Handle to cache object
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Free all objects within the requested cache and delete the
+ * cache object.
+ *
+ ******************************************************************************/
+
+acpi_status acpi_os_delete_cache(struct acpi_memory_list * cache)
+{
+ acpi_status status;
+
+ ACPI_FUNCTION_ENTRY();
+
+ /* Purge all objects in the cache */
+
+ status = acpi_os_purge_cache(cache);
+ if (ACPI_FAILURE(status)) {
+ return (status);
+ }
+
+ /* Now we can delete the cache object */
+
+ acpi_os_free(cache);
+ return (AE_OK);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_os_release_object
+ *
+ * PARAMETERS: Cache - Handle to cache object
+ * Object - The object to be released
+ *
+ * RETURN: None
+ *
+ * DESCRIPTION: Release an object to the specified cache. If cache is full,
+ * the object is deleted.
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_os_release_object(struct acpi_memory_list * cache, void *object)
+{
+ acpi_status status;
+
+ ACPI_FUNCTION_ENTRY();
+
+ if (!cache || !object) {
+ return (AE_BAD_PARAMETER);
+ }
+
+ /* If cache is full, just free this object */
+
+ if (cache->current_depth >= cache->max_depth) {
+ ACPI_MEM_FREE(object);
+ ACPI_MEM_TRACKING(cache->total_freed++);
+ }
+
+ /* Otherwise put this object back into the cache */
+
+ else {
+ status = acpi_ut_acquire_mutex(ACPI_MTX_CACHES);
+ if (ACPI_FAILURE(status)) {
+ return (status);
+ }
+
+ /* Mark the object as cached */
+
+ ACPI_MEMSET(object, 0xCA, cache->object_size);
+ ACPI_SET_DESCRIPTOR_TYPE(object, ACPI_DESC_TYPE_CACHED);
+
+ /* Put the object at the head of the cache list */
+
+ *(ACPI_CAST_INDIRECT_PTR(char,
+ &(((char *)object)[cache->
+ link_offset]))) =
+ cache->list_head;
+ cache->list_head = object;
+ cache->current_depth++;
+
+ (void)acpi_ut_release_mutex(ACPI_MTX_CACHES);
+ }
+
+ return (AE_OK);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_os_acquire_object
+ *
+ * PARAMETERS: Cache - Handle to cache object
+ *
+ * RETURN: the acquired object. NULL on error
+ *
+ * DESCRIPTION: Get an object from the specified cache. If cache is empty,
+ * the object is allocated.
+ *
+ ******************************************************************************/
+
+void *acpi_os_acquire_object(struct acpi_memory_list *cache)
+{
+ acpi_status status;
+ void *object;
+
+ ACPI_FUNCTION_NAME("os_acquire_object");
+
+ if (!cache) {
+ return (NULL);
+ }
+
+ status = acpi_ut_acquire_mutex(ACPI_MTX_CACHES);
+ if (ACPI_FAILURE(status)) {
+ return (NULL);
+ }
+
+ ACPI_MEM_TRACKING(cache->requests++);
+
+ /* Check the cache first */
+
+ if (cache->list_head) {
+ /* There is an object available, use it */
+
+ object = cache->list_head;
+ cache->list_head = *(ACPI_CAST_INDIRECT_PTR(char,
+ &(((char *)
+ object)[cache->
+ link_offset])));
+
+ cache->current_depth--;
+
+ ACPI_MEM_TRACKING(cache->hits++);
+ ACPI_MEM_TRACKING(ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
+ "Object %p from %s cache\n",
+ object, cache->list_name)));
+
+ status = acpi_ut_release_mutex(ACPI_MTX_CACHES);
+ if (ACPI_FAILURE(status)) {
+ return (NULL);
+ }
+
+ /* Clear (zero) the previously used Object */
+
+ ACPI_MEMSET(object, 0, cache->object_size);
+ } else {
+ /* The cache is empty, create a new object */
+
+ ACPI_MEM_TRACKING(cache->total_allocated++);
+
+ /* Avoid deadlock with ACPI_MEM_CALLOCATE */
+
+ status = acpi_ut_release_mutex(ACPI_MTX_CACHES);
+ if (ACPI_FAILURE(status)) {
+ return (NULL);
+ }
+
+ object = ACPI_MEM_CALLOCATE(cache->object_size);
+ if (!object) {
+ return (NULL);
+ }
+ }
+
+ return (object);
+}
+#endif /* ACPI_USE_LOCAL_CACHE */
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