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1 /*******************************************************************************
2  *
3  * Module Name: utmutex - local mutex support
4  *
5  ******************************************************************************/
6
7 /*
8  * Copyright (C) 2000 - 2013, 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
48 ACPI_MODULE_NAME("utmutex")
49
50 /* Local prototypes */
51 static acpi_status acpi_ut_create_mutex(acpi_mutex_handle mutex_id);
52
53 static 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
68 acpi_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 */
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         /* Mutex for _OSI support */
97         status = acpi_os_create_mutex(&acpi_gbl_osi_mutex);
98         if (ACPI_FAILURE(status)) {
99                 return_ACPI_STATUS(status);
100         }
101
102         /* Create the reader/writer lock for namespace access */
103
104         status = acpi_ut_create_rw_lock(&acpi_gbl_namespace_rw_lock);
105         return_ACPI_STATUS(status);
106 }
107
108 /*******************************************************************************
109  *
110  * FUNCTION:    acpi_ut_mutex_terminate
111  *
112  * PARAMETERS:  None.
113  *
114  * RETURN:      None.
115  *
116  * DESCRIPTION: Delete all of the system mutex objects. This includes mutexes,
117  *              spin locks, and reader/writer locks.
118  *
119  ******************************************************************************/
120
121 void acpi_ut_mutex_terminate(void)
122 {
123         u32 i;
124
125         ACPI_FUNCTION_TRACE(ut_mutex_terminate);
126
127         /* Delete each predefined mutex object */
128
129         for (i = 0; i < ACPI_NUM_MUTEX; i++) {
130                 acpi_ut_delete_mutex(i);
131         }
132
133         acpi_os_delete_mutex(acpi_gbl_osi_mutex);
134
135         /* Delete the spinlocks */
136
137         acpi_os_delete_lock(acpi_gbl_gpe_lock);
138         acpi_os_delete_lock(acpi_gbl_hardware_lock);
139
140         /* Delete the reader/writer lock */
141
142         acpi_ut_delete_rw_lock(&acpi_gbl_namespace_rw_lock);
143         return_VOID;
144 }
145
146 /*******************************************************************************
147  *
148  * FUNCTION:    acpi_ut_create_mutex
149  *
150  * PARAMETERS:  mutex_ID        - ID of the mutex to be created
151  *
152  * RETURN:      Status
153  *
154  * DESCRIPTION: Create a mutex object.
155  *
156  ******************************************************************************/
157
158 static acpi_status acpi_ut_create_mutex(acpi_mutex_handle mutex_id)
159 {
160         acpi_status status = AE_OK;
161
162         ACPI_FUNCTION_TRACE_U32(ut_create_mutex, mutex_id);
163
164         if (!acpi_gbl_mutex_info[mutex_id].mutex) {
165                 status =
166                     acpi_os_create_mutex(&acpi_gbl_mutex_info[mutex_id].mutex);
167                 acpi_gbl_mutex_info[mutex_id].thread_id =
168                     ACPI_MUTEX_NOT_ACQUIRED;
169                 acpi_gbl_mutex_info[mutex_id].use_count = 0;
170         }
171
172         return_ACPI_STATUS(status);
173 }
174
175 /*******************************************************************************
176  *
177  * FUNCTION:    acpi_ut_delete_mutex
178  *
179  * PARAMETERS:  mutex_ID        - ID of the mutex to be deleted
180  *
181  * RETURN:      Status
182  *
183  * DESCRIPTION: Delete a mutex object.
184  *
185  ******************************************************************************/
186
187 static void acpi_ut_delete_mutex(acpi_mutex_handle mutex_id)
188 {
189
190         ACPI_FUNCTION_TRACE_U32(ut_delete_mutex, mutex_id);
191
192         acpi_os_delete_mutex(acpi_gbl_mutex_info[mutex_id].mutex);
193
194         acpi_gbl_mutex_info[mutex_id].mutex = NULL;
195         acpi_gbl_mutex_info[mutex_id].thread_id = ACPI_MUTEX_NOT_ACQUIRED;
196
197         return_VOID;
198 }
199
200 /*******************************************************************************
201  *
202  * FUNCTION:    acpi_ut_acquire_mutex
203  *
204  * PARAMETERS:  mutex_ID        - ID of the mutex to be acquired
205  *
206  * RETURN:      Status
207  *
208  * DESCRIPTION: Acquire a mutex object.
209  *
210  ******************************************************************************/
211
212 acpi_status acpi_ut_acquire_mutex(acpi_mutex_handle mutex_id)
213 {
214         acpi_status status;
215         acpi_thread_id this_thread_id;
216
217         ACPI_FUNCTION_NAME(ut_acquire_mutex);
218
219         if (mutex_id > ACPI_MAX_MUTEX) {
220                 return (AE_BAD_PARAMETER);
221         }
222
223         this_thread_id = acpi_os_get_thread_id();
224
225 #ifdef ACPI_MUTEX_DEBUG
226         {
227                 u32 i;
228                 /*
229                  * Mutex debug code, for internal debugging only.
230                  *
231                  * Deadlock prevention. Check if this thread owns any mutexes of value
232                  * greater than or equal to this one. If so, the thread has violated
233                  * the mutex ordering rule. This indicates a coding error somewhere in
234                  * the ACPI subsystem code.
235                  */
236                 for (i = mutex_id; i < ACPI_NUM_MUTEX; i++) {
237                         if (acpi_gbl_mutex_info[i].thread_id == this_thread_id) {
238                                 if (i == mutex_id) {
239                                         ACPI_ERROR((AE_INFO,
240                                                     "Mutex [%s] already acquired by this thread [%u]",
241                                                     acpi_ut_get_mutex_name
242                                                     (mutex_id),
243                                                     (u32)this_thread_id));
244
245                                         return (AE_ALREADY_ACQUIRED);
246                                 }
247
248                                 ACPI_ERROR((AE_INFO,
249                                             "Invalid acquire order: Thread %u owns [%s], wants [%s]",
250                                             (u32)this_thread_id,
251                                             acpi_ut_get_mutex_name(i),
252                                             acpi_ut_get_mutex_name(mutex_id)));
253
254                                 return (AE_ACQUIRE_DEADLOCK);
255                         }
256                 }
257         }
258 #endif
259
260         ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
261                           "Thread %u attempting to acquire Mutex [%s]\n",
262                           (u32)this_thread_id,
263                           acpi_ut_get_mutex_name(mutex_id)));
264
265         status = acpi_os_acquire_mutex(acpi_gbl_mutex_info[mutex_id].mutex,
266                                        ACPI_WAIT_FOREVER);
267         if (ACPI_SUCCESS(status)) {
268                 ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
269                                   "Thread %u acquired Mutex [%s]\n",
270                                   (u32)this_thread_id,
271                                   acpi_ut_get_mutex_name(mutex_id)));
272
273                 acpi_gbl_mutex_info[mutex_id].use_count++;
274                 acpi_gbl_mutex_info[mutex_id].thread_id = this_thread_id;
275         } else {
276                 ACPI_EXCEPTION((AE_INFO, status,
277                                 "Thread %u could not acquire Mutex [0x%X]",
278                                 (u32)this_thread_id, mutex_id));
279         }
280
281         return (status);
282 }
283
284 /*******************************************************************************
285  *
286  * FUNCTION:    acpi_ut_release_mutex
287  *
288  * PARAMETERS:  mutex_ID        - ID of the mutex to be released
289  *
290  * RETURN:      Status
291  *
292  * DESCRIPTION: Release a mutex object.
293  *
294  ******************************************************************************/
295
296 acpi_status acpi_ut_release_mutex(acpi_mutex_handle mutex_id)
297 {
298         ACPI_FUNCTION_NAME(ut_release_mutex);
299
300         ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Thread %u releasing Mutex [%s]\n",
301                           (u32)acpi_os_get_thread_id(),
302                           acpi_ut_get_mutex_name(mutex_id)));
303
304         if (mutex_id > ACPI_MAX_MUTEX) {
305                 return (AE_BAD_PARAMETER);
306         }
307
308         /*
309          * Mutex must be acquired in order to release it!
310          */
311         if (acpi_gbl_mutex_info[mutex_id].thread_id == ACPI_MUTEX_NOT_ACQUIRED) {
312                 ACPI_ERROR((AE_INFO,
313                             "Mutex [0x%X] is not acquired, cannot release",
314                             mutex_id));
315
316                 return (AE_NOT_ACQUIRED);
317         }
318 #ifdef ACPI_MUTEX_DEBUG
319         {
320                 u32 i;
321                 /*
322                  * Mutex debug code, for internal debugging only.
323                  *
324                  * Deadlock prevention. Check if this thread owns any mutexes of value
325                  * greater than this one. If so, the thread has violated the mutex
326                  * ordering rule. This indicates a coding error somewhere in
327                  * the ACPI subsystem code.
328                  */
329                 for (i = mutex_id; i < ACPI_NUM_MUTEX; i++) {
330                         if (acpi_gbl_mutex_info[i].thread_id ==
331                             acpi_os_get_thread_id()) {
332                                 if (i == mutex_id) {
333                                         continue;
334                                 }
335
336                                 ACPI_ERROR((AE_INFO,
337                                             "Invalid release order: owns [%s], releasing [%s]",
338                                             acpi_ut_get_mutex_name(i),
339                                             acpi_ut_get_mutex_name(mutex_id)));
340
341                                 return (AE_RELEASE_DEADLOCK);
342                         }
343                 }
344         }
345 #endif
346
347         /* Mark unlocked FIRST */
348
349         acpi_gbl_mutex_info[mutex_id].thread_id = ACPI_MUTEX_NOT_ACQUIRED;
350
351         acpi_os_release_mutex(acpi_gbl_mutex_info[mutex_id].mutex);
352         return (AE_OK);
353 }