1/*******************************************************************************
2 *
3 * Module Name: utmutex - local mutex support
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("utmutex")
49
50/* Local prototypes */
51static acpi_status acpi_ut_create_mutex(acpi_mutex_handle mutex_id);
52
53static void acpi_ut_delete_mutex(acpi_mutex_handle mutex_id);
54
55/*******************************************************************************
56 *
57 * FUNCTION:    acpi_ut_mutex_initialize
58 *
59 * PARAMETERS:  None.
60 *
61 * RETURN:      Status
62 *
63 * DESCRIPTION: Create the system mutex objects. This includes mutexes,
64 *              spin locks, and reader/writer locks.
65 *
66 ******************************************************************************/
67
68acpi_status acpi_ut_mutex_initialize(void)
69{
70	u32 i;
71	acpi_status status;
72
73	ACPI_FUNCTION_TRACE(ut_mutex_initialize);
74
75	/* Create each of the predefined mutex objects */
76
77	for (i = 0; i < ACPI_NUM_MUTEX; i++) {
78		status = acpi_ut_create_mutex(i);
79		if (ACPI_FAILURE(status)) {
80			return_ACPI_STATUS(status);
81		}
82	}
83
84	/* Create the spinlocks for use at interrupt level or for speed */
85
86	status = acpi_os_create_lock (&acpi_gbl_gpe_lock);
87	if (ACPI_FAILURE (status)) {
88		return_ACPI_STATUS (status);
89	}
90
91	status = acpi_os_create_lock (&acpi_gbl_hardware_lock);
92	if (ACPI_FAILURE (status)) {
93		return_ACPI_STATUS (status);
94	}
95
96	status = acpi_os_create_lock(&acpi_gbl_reference_count_lock);
97	if (ACPI_FAILURE(status)) {
98		return_ACPI_STATUS(status);
99	}
100
101	/* Mutex for _OSI support */
102
103	status = acpi_os_create_mutex(&acpi_gbl_osi_mutex);
104	if (ACPI_FAILURE(status)) {
105		return_ACPI_STATUS(status);
106	}
107
108	/* Create the reader/writer lock for namespace access */
109
110	status = acpi_ut_create_rw_lock(&acpi_gbl_namespace_rw_lock);
111	return_ACPI_STATUS(status);
112}
113
114/*******************************************************************************
115 *
116 * FUNCTION:    acpi_ut_mutex_terminate
117 *
118 * PARAMETERS:  None.
119 *
120 * RETURN:      None.
121 *
122 * DESCRIPTION: Delete all of the system mutex objects. This includes mutexes,
123 *              spin locks, and reader/writer locks.
124 *
125 ******************************************************************************/
126
127void acpi_ut_mutex_terminate(void)
128{
129	u32 i;
130
131	ACPI_FUNCTION_TRACE(ut_mutex_terminate);
132
133	/* Delete each predefined mutex object */
134
135	for (i = 0; i < ACPI_NUM_MUTEX; i++) {
136		acpi_ut_delete_mutex(i);
137	}
138
139	acpi_os_delete_mutex(acpi_gbl_osi_mutex);
140
141	/* Delete the spinlocks */
142
143	acpi_os_delete_lock(acpi_gbl_gpe_lock);
144	acpi_os_delete_lock(acpi_gbl_hardware_lock);
145	acpi_os_delete_lock(acpi_gbl_reference_count_lock);
146
147	/* Delete the reader/writer lock */
148
149	acpi_ut_delete_rw_lock(&acpi_gbl_namespace_rw_lock);
150	return_VOID;
151}
152
153/*******************************************************************************
154 *
155 * FUNCTION:    acpi_ut_create_mutex
156 *
157 * PARAMETERS:  mutex_ID        - ID of the mutex to be created
158 *
159 * RETURN:      Status
160 *
161 * DESCRIPTION: Create a mutex object.
162 *
163 ******************************************************************************/
164
165static acpi_status acpi_ut_create_mutex(acpi_mutex_handle mutex_id)
166{
167	acpi_status status = AE_OK;
168
169	ACPI_FUNCTION_TRACE_U32(ut_create_mutex, mutex_id);
170
171	if (!acpi_gbl_mutex_info[mutex_id].mutex) {
172		status =
173		    acpi_os_create_mutex(&acpi_gbl_mutex_info[mutex_id].mutex);
174		acpi_gbl_mutex_info[mutex_id].thread_id =
175		    ACPI_MUTEX_NOT_ACQUIRED;
176		acpi_gbl_mutex_info[mutex_id].use_count = 0;
177	}
178
179	return_ACPI_STATUS(status);
180}
181
182/*******************************************************************************
183 *
184 * FUNCTION:    acpi_ut_delete_mutex
185 *
186 * PARAMETERS:  mutex_ID        - ID of the mutex to be deleted
187 *
188 * RETURN:      Status
189 *
190 * DESCRIPTION: Delete a mutex object.
191 *
192 ******************************************************************************/
193
194static void acpi_ut_delete_mutex(acpi_mutex_handle mutex_id)
195{
196
197	ACPI_FUNCTION_TRACE_U32(ut_delete_mutex, mutex_id);
198
199	acpi_os_delete_mutex(acpi_gbl_mutex_info[mutex_id].mutex);
200
201	acpi_gbl_mutex_info[mutex_id].mutex = NULL;
202	acpi_gbl_mutex_info[mutex_id].thread_id = ACPI_MUTEX_NOT_ACQUIRED;
203
204	return_VOID;
205}
206
207/*******************************************************************************
208 *
209 * FUNCTION:    acpi_ut_acquire_mutex
210 *
211 * PARAMETERS:  mutex_ID        - ID of the mutex to be acquired
212 *
213 * RETURN:      Status
214 *
215 * DESCRIPTION: Acquire a mutex object.
216 *
217 ******************************************************************************/
218
219acpi_status acpi_ut_acquire_mutex(acpi_mutex_handle mutex_id)
220{
221	acpi_status status;
222	acpi_thread_id this_thread_id;
223
224	ACPI_FUNCTION_NAME(ut_acquire_mutex);
225
226	if (mutex_id > ACPI_MAX_MUTEX) {
227		return (AE_BAD_PARAMETER);
228	}
229
230	this_thread_id = acpi_os_get_thread_id();
231
232#ifdef ACPI_MUTEX_DEBUG
233	{
234		u32 i;
235		/*
236		 * Mutex debug code, for internal debugging only.
237		 *
238		 * Deadlock prevention. Check if this thread owns any mutexes of value
239		 * greater than or equal to this one. If so, the thread has violated
240		 * the mutex ordering rule. This indicates a coding error somewhere in
241		 * the ACPI subsystem code.
242		 */
243		for (i = mutex_id; i < ACPI_NUM_MUTEX; i++) {
244			if (acpi_gbl_mutex_info[i].thread_id == this_thread_id) {
245				if (i == mutex_id) {
246					ACPI_ERROR((AE_INFO,
247						    "Mutex [%s] already acquired by this thread [%u]",
248						    acpi_ut_get_mutex_name
249						    (mutex_id),
250						    (u32)this_thread_id));
251
252					return (AE_ALREADY_ACQUIRED);
253				}
254
255				ACPI_ERROR((AE_INFO,
256					    "Invalid acquire order: Thread %u owns [%s], wants [%s]",
257					    (u32)this_thread_id,
258					    acpi_ut_get_mutex_name(i),
259					    acpi_ut_get_mutex_name(mutex_id)));
260
261				return (AE_ACQUIRE_DEADLOCK);
262			}
263		}
264	}
265#endif
266
267	ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
268			  "Thread %u attempting to acquire Mutex [%s]\n",
269			  (u32)this_thread_id,
270			  acpi_ut_get_mutex_name(mutex_id)));
271
272	status = acpi_os_acquire_mutex(acpi_gbl_mutex_info[mutex_id].mutex,
273				       ACPI_WAIT_FOREVER);
274	if (ACPI_SUCCESS(status)) {
275		ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
276				  "Thread %u acquired Mutex [%s]\n",
277				  (u32)this_thread_id,
278				  acpi_ut_get_mutex_name(mutex_id)));
279
280		acpi_gbl_mutex_info[mutex_id].use_count++;
281		acpi_gbl_mutex_info[mutex_id].thread_id = this_thread_id;
282	} else {
283		ACPI_EXCEPTION((AE_INFO, status,
284				"Thread %u could not acquire Mutex [0x%X]",
285				(u32)this_thread_id, mutex_id));
286	}
287
288	return (status);
289}
290
291/*******************************************************************************
292 *
293 * FUNCTION:    acpi_ut_release_mutex
294 *
295 * PARAMETERS:  mutex_ID        - ID of the mutex to be released
296 *
297 * RETURN:      Status
298 *
299 * DESCRIPTION: Release a mutex object.
300 *
301 ******************************************************************************/
302
303acpi_status acpi_ut_release_mutex(acpi_mutex_handle mutex_id)
304{
305	ACPI_FUNCTION_NAME(ut_release_mutex);
306
307	ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Thread %u releasing Mutex [%s]\n",
308			  (u32)acpi_os_get_thread_id(),
309			  acpi_ut_get_mutex_name(mutex_id)));
310
311	if (mutex_id > ACPI_MAX_MUTEX) {
312		return (AE_BAD_PARAMETER);
313	}
314
315	/*
316	 * Mutex must be acquired in order to release it!
317	 */
318	if (acpi_gbl_mutex_info[mutex_id].thread_id == ACPI_MUTEX_NOT_ACQUIRED) {
319		ACPI_ERROR((AE_INFO,
320			    "Mutex [0x%X] is not acquired, cannot release",
321			    mutex_id));
322
323		return (AE_NOT_ACQUIRED);
324	}
325#ifdef ACPI_MUTEX_DEBUG
326	{
327		u32 i;
328		/*
329		 * Mutex debug code, for internal debugging only.
330		 *
331		 * Deadlock prevention. Check if this thread owns any mutexes of value
332		 * greater than this one. If so, the thread has violated the mutex
333		 * ordering rule. This indicates a coding error somewhere in
334		 * the ACPI subsystem code.
335		 */
336		for (i = mutex_id; i < ACPI_NUM_MUTEX; i++) {
337			if (acpi_gbl_mutex_info[i].thread_id ==
338			    acpi_os_get_thread_id()) {
339				if (i == mutex_id) {
340					continue;
341				}
342
343				ACPI_ERROR((AE_INFO,
344					    "Invalid release order: owns [%s], releasing [%s]",
345					    acpi_ut_get_mutex_name(i),
346					    acpi_ut_get_mutex_name(mutex_id)));
347
348				return (AE_RELEASE_DEADLOCK);
349			}
350		}
351	}
352#endif
353
354	/* Mark unlocked FIRST */
355
356	acpi_gbl_mutex_info[mutex_id].thread_id = ACPI_MUTEX_NOT_ACQUIRED;
357
358	acpi_os_release_mutex(acpi_gbl_mutex_info[mutex_id].mutex);
359	return (AE_OK);
360}
361