1/******************************************************************************
2 *
3 * Module Name: utcache - local cache allocation routines
4 *
5 *****************************************************************************/
6
7/*
8 * Copyright (C) 2000 - 2014, Intel Corp.
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
44#include <acpi/acpi.h>
45#include "accommon.h"
46
47#define _COMPONENT          ACPI_UTILITIES
48ACPI_MODULE_NAME("utcache")
49
50#ifdef ACPI_USE_LOCAL_CACHE
51/*******************************************************************************
52 *
53 * FUNCTION:    acpi_os_create_cache
54 *
55 * PARAMETERS:  cache_name      - Ascii name for the cache
56 *              object_size     - Size of each cached object
57 *              max_depth       - Maximum depth of the cache (in objects)
58 *              return_cache    - Where the new cache object is returned
59 *
60 * RETURN:      Status
61 *
62 * DESCRIPTION: Create a cache object
63 *
64 ******************************************************************************/
65acpi_status
66acpi_os_create_cache(char *cache_name,
67		     u16 object_size,
68		     u16 max_depth, struct acpi_memory_list **return_cache)
69{
70	struct acpi_memory_list *cache;
71
72	ACPI_FUNCTION_ENTRY();
73
74	if (!cache_name || !return_cache || (object_size < 16)) {
75		return (AE_BAD_PARAMETER);
76	}
77
78	/* Create the cache object */
79
80	cache = acpi_os_allocate(sizeof(struct acpi_memory_list));
81	if (!cache) {
82		return (AE_NO_MEMORY);
83	}
84
85	/* Populate the cache object and return it */
86
87	ACPI_MEMSET(cache, 0, sizeof(struct acpi_memory_list));
88	cache->list_name = cache_name;
89	cache->object_size = object_size;
90	cache->max_depth = max_depth;
91
92	*return_cache = cache;
93	return (AE_OK);
94}
95
96/*******************************************************************************
97 *
98 * FUNCTION:    acpi_os_purge_cache
99 *
100 * PARAMETERS:  cache           - Handle to cache object
101 *
102 * RETURN:      Status
103 *
104 * DESCRIPTION: Free all objects within the requested cache.
105 *
106 ******************************************************************************/
107
108acpi_status acpi_os_purge_cache(struct acpi_memory_list * cache)
109{
110	void *next;
111	acpi_status status;
112
113	ACPI_FUNCTION_ENTRY();
114
115	if (!cache) {
116		return (AE_BAD_PARAMETER);
117	}
118
119	status = acpi_ut_acquire_mutex(ACPI_MTX_CACHES);
120	if (ACPI_FAILURE(status)) {
121		return (status);
122	}
123
124	/* Walk the list of objects in this cache */
125
126	while (cache->list_head) {
127
128		/* Delete and unlink one cached state object */
129
130		next = ACPI_GET_DESCRIPTOR_PTR(cache->list_head);
131		ACPI_FREE(cache->list_head);
132
133		cache->list_head = next;
134		cache->current_depth--;
135	}
136
137	(void)acpi_ut_release_mutex(ACPI_MTX_CACHES);
138	return (AE_OK);
139}
140
141/*******************************************************************************
142 *
143 * FUNCTION:    acpi_os_delete_cache
144 *
145 * PARAMETERS:  cache           - Handle to cache object
146 *
147 * RETURN:      Status
148 *
149 * DESCRIPTION: Free all objects within the requested cache and delete the
150 *              cache object.
151 *
152 ******************************************************************************/
153
154acpi_status acpi_os_delete_cache(struct acpi_memory_list * cache)
155{
156	acpi_status status;
157
158	ACPI_FUNCTION_ENTRY();
159
160	/* Purge all objects in the cache */
161
162	status = acpi_os_purge_cache(cache);
163	if (ACPI_FAILURE(status)) {
164		return (status);
165	}
166
167	/* Now we can delete the cache object */
168
169	acpi_os_free(cache);
170	return (AE_OK);
171}
172
173/*******************************************************************************
174 *
175 * FUNCTION:    acpi_os_release_object
176 *
177 * PARAMETERS:  cache       - Handle to cache object
178 *              object      - The object to be released
179 *
180 * RETURN:      None
181 *
182 * DESCRIPTION: Release an object to the specified cache. If cache is full,
183 *              the object is deleted.
184 *
185 ******************************************************************************/
186
187acpi_status
188acpi_os_release_object(struct acpi_memory_list * cache, void *object)
189{
190	acpi_status status;
191
192	ACPI_FUNCTION_ENTRY();
193
194	if (!cache || !object) {
195		return (AE_BAD_PARAMETER);
196	}
197
198	/* If cache is full, just free this object */
199
200	if (cache->current_depth >= cache->max_depth) {
201		ACPI_FREE(object);
202		ACPI_MEM_TRACKING(cache->total_freed++);
203	}
204
205	/* Otherwise put this object back into the cache */
206
207	else {
208		status = acpi_ut_acquire_mutex(ACPI_MTX_CACHES);
209		if (ACPI_FAILURE(status)) {
210			return (status);
211		}
212
213		/* Mark the object as cached */
214
215		ACPI_MEMSET(object, 0xCA, cache->object_size);
216		ACPI_SET_DESCRIPTOR_TYPE(object, ACPI_DESC_TYPE_CACHED);
217
218		/* Put the object at the head of the cache list */
219
220		ACPI_SET_DESCRIPTOR_PTR(object, cache->list_head);
221		cache->list_head = object;
222		cache->current_depth++;
223
224		(void)acpi_ut_release_mutex(ACPI_MTX_CACHES);
225	}
226
227	return (AE_OK);
228}
229
230/*******************************************************************************
231 *
232 * FUNCTION:    acpi_os_acquire_object
233 *
234 * PARAMETERS:  cache           - Handle to cache object
235 *
236 * RETURN:      the acquired object. NULL on error
237 *
238 * DESCRIPTION: Get an object from the specified cache. If cache is empty,
239 *              the object is allocated.
240 *
241 ******************************************************************************/
242
243void *acpi_os_acquire_object(struct acpi_memory_list *cache)
244{
245	acpi_status status;
246	void *object;
247
248	ACPI_FUNCTION_NAME(os_acquire_object);
249
250	if (!cache) {
251		return_PTR(NULL);
252	}
253
254	status = acpi_ut_acquire_mutex(ACPI_MTX_CACHES);
255	if (ACPI_FAILURE(status)) {
256		return_PTR(NULL);
257	}
258
259	ACPI_MEM_TRACKING(cache->requests++);
260
261	/* Check the cache first */
262
263	if (cache->list_head) {
264
265		/* There is an object available, use it */
266
267		object = cache->list_head;
268		cache->list_head = ACPI_GET_DESCRIPTOR_PTR(object);
269
270		cache->current_depth--;
271
272		ACPI_MEM_TRACKING(cache->hits++);
273		ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
274				  "Object %p from %s cache\n", object,
275				  cache->list_name));
276
277		status = acpi_ut_release_mutex(ACPI_MTX_CACHES);
278		if (ACPI_FAILURE(status)) {
279			return_PTR(NULL);
280		}
281
282		/* Clear (zero) the previously used Object */
283
284		ACPI_MEMSET(object, 0, cache->object_size);
285	} else {
286		/* The cache is empty, create a new object */
287
288		ACPI_MEM_TRACKING(cache->total_allocated++);
289
290#ifdef ACPI_DBG_TRACK_ALLOCATIONS
291		if ((cache->total_allocated - cache->total_freed) >
292		    cache->max_occupied) {
293			cache->max_occupied =
294			    cache->total_allocated - cache->total_freed;
295		}
296#endif
297
298		/* Avoid deadlock with ACPI_ALLOCATE_ZEROED */
299
300		status = acpi_ut_release_mutex(ACPI_MTX_CACHES);
301		if (ACPI_FAILURE(status)) {
302			return_PTR(NULL);
303		}
304
305		object = ACPI_ALLOCATE_ZEROED(cache->object_size);
306		if (!object) {
307			return_PTR(NULL);
308		}
309	}
310
311	return_PTR(object);
312}
313#endif				/* ACPI_USE_LOCAL_CACHE */
314