Linux-libre 4.14.68-gnu
[librecmc/linux-libre.git] / drivers / acpi / acpica / utmutex.c
1 /*******************************************************************************
2  *
3  * Module Name: utmutex - local mutex support
4  *
5  ******************************************************************************/
6
7 /*
8  * Copyright (C) 2000 - 2017, 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 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         if (ACPI_FAILURE(status)) {
112                 return_ACPI_STATUS(status);
113         }
114
115         return_ACPI_STATUS(status);
116 }
117
118 /*******************************************************************************
119  *
120  * FUNCTION:    acpi_ut_mutex_terminate
121  *
122  * PARAMETERS:  None.
123  *
124  * RETURN:      None.
125  *
126  * DESCRIPTION: Delete all of the system mutex objects. This includes mutexes,
127  *              spin locks, and reader/writer locks.
128  *
129  ******************************************************************************/
130
131 void acpi_ut_mutex_terminate(void)
132 {
133         u32 i;
134
135         ACPI_FUNCTION_TRACE(ut_mutex_terminate);
136
137         /* Delete each predefined mutex object */
138
139         for (i = 0; i < ACPI_NUM_MUTEX; i++) {
140                 acpi_ut_delete_mutex(i);
141         }
142
143         acpi_os_delete_mutex(acpi_gbl_osi_mutex);
144
145         /* Delete the spinlocks */
146
147         acpi_os_delete_lock(acpi_gbl_gpe_lock);
148         acpi_os_delete_lock(acpi_gbl_hardware_lock);
149         acpi_os_delete_lock(acpi_gbl_reference_count_lock);
150
151         /* Delete the reader/writer lock */
152
153         acpi_ut_delete_rw_lock(&acpi_gbl_namespace_rw_lock);
154         return_VOID;
155 }
156
157 /*******************************************************************************
158  *
159  * FUNCTION:    acpi_ut_create_mutex
160  *
161  * PARAMETERS:  mutex_ID        - ID of the mutex to be created
162  *
163  * RETURN:      Status
164  *
165  * DESCRIPTION: Create a mutex object.
166  *
167  ******************************************************************************/
168
169 static acpi_status acpi_ut_create_mutex(acpi_mutex_handle mutex_id)
170 {
171         acpi_status status = AE_OK;
172
173         ACPI_FUNCTION_TRACE_U32(ut_create_mutex, mutex_id);
174
175         if (!acpi_gbl_mutex_info[mutex_id].mutex) {
176                 status =
177                     acpi_os_create_mutex(&acpi_gbl_mutex_info[mutex_id].mutex);
178                 acpi_gbl_mutex_info[mutex_id].thread_id =
179                     ACPI_MUTEX_NOT_ACQUIRED;
180                 acpi_gbl_mutex_info[mutex_id].use_count = 0;
181         }
182
183         return_ACPI_STATUS(status);
184 }
185
186 /*******************************************************************************
187  *
188  * FUNCTION:    acpi_ut_delete_mutex
189  *
190  * PARAMETERS:  mutex_ID        - ID of the mutex to be deleted
191  *
192  * RETURN:      Status
193  *
194  * DESCRIPTION: Delete a mutex object.
195  *
196  ******************************************************************************/
197
198 static void acpi_ut_delete_mutex(acpi_mutex_handle mutex_id)
199 {
200
201         ACPI_FUNCTION_TRACE_U32(ut_delete_mutex, mutex_id);
202
203         acpi_os_delete_mutex(acpi_gbl_mutex_info[mutex_id].mutex);
204
205         acpi_gbl_mutex_info[mutex_id].mutex = NULL;
206         acpi_gbl_mutex_info[mutex_id].thread_id = ACPI_MUTEX_NOT_ACQUIRED;
207
208         return_VOID;
209 }
210
211 /*******************************************************************************
212  *
213  * FUNCTION:    acpi_ut_acquire_mutex
214  *
215  * PARAMETERS:  mutex_ID        - ID of the mutex to be acquired
216  *
217  * RETURN:      Status
218  *
219  * DESCRIPTION: Acquire a mutex object.
220  *
221  ******************************************************************************/
222
223 acpi_status acpi_ut_acquire_mutex(acpi_mutex_handle mutex_id)
224 {
225         acpi_status status;
226         acpi_thread_id this_thread_id;
227
228         ACPI_FUNCTION_NAME(ut_acquire_mutex);
229
230         if (mutex_id > ACPI_MAX_MUTEX) {
231                 return (AE_BAD_PARAMETER);
232         }
233
234         this_thread_id = acpi_os_get_thread_id();
235
236 #ifdef ACPI_MUTEX_DEBUG
237         {
238                 u32 i;
239                 /*
240                  * Mutex debug code, for internal debugging only.
241                  *
242                  * Deadlock prevention. Check if this thread owns any mutexes of value
243                  * greater than or equal to this one. If so, the thread has violated
244                  * the mutex ordering rule. This indicates a coding error somewhere in
245                  * the ACPI subsystem code.
246                  */
247                 for (i = mutex_id; i < ACPI_NUM_MUTEX; i++) {
248                         if (acpi_gbl_mutex_info[i].thread_id == this_thread_id) {
249                                 if (i == mutex_id) {
250                                         ACPI_ERROR((AE_INFO,
251                                                     "Mutex [%s] already acquired by this thread [%u]",
252                                                     acpi_ut_get_mutex_name
253                                                     (mutex_id),
254                                                     (u32)this_thread_id));
255
256                                         return (AE_ALREADY_ACQUIRED);
257                                 }
258
259                                 ACPI_ERROR((AE_INFO,
260                                             "Invalid acquire order: Thread %u owns [%s], wants [%s]",
261                                             (u32)this_thread_id,
262                                             acpi_ut_get_mutex_name(i),
263                                             acpi_ut_get_mutex_name(mutex_id)));
264
265                                 return (AE_ACQUIRE_DEADLOCK);
266                         }
267                 }
268         }
269 #endif
270
271         ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
272                           "Thread %u attempting to acquire Mutex [%s]\n",
273                           (u32)this_thread_id,
274                           acpi_ut_get_mutex_name(mutex_id)));
275
276         status =
277             acpi_os_acquire_mutex(acpi_gbl_mutex_info[mutex_id].mutex,
278                                   ACPI_WAIT_FOREVER);
279         if (ACPI_SUCCESS(status)) {
280                 ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
281                                   "Thread %u acquired Mutex [%s]\n",
282                                   (u32)this_thread_id,
283                                   acpi_ut_get_mutex_name(mutex_id)));
284
285                 acpi_gbl_mutex_info[mutex_id].use_count++;
286                 acpi_gbl_mutex_info[mutex_id].thread_id = this_thread_id;
287         } else {
288                 ACPI_EXCEPTION((AE_INFO, status,
289                                 "Thread %u could not acquire Mutex [0x%X]",
290                                 (u32)this_thread_id, mutex_id));
291         }
292
293         return (status);
294 }
295
296 /*******************************************************************************
297  *
298  * FUNCTION:    acpi_ut_release_mutex
299  *
300  * PARAMETERS:  mutex_ID        - ID of the mutex to be released
301  *
302  * RETURN:      Status
303  *
304  * DESCRIPTION: Release a mutex object.
305  *
306  ******************************************************************************/
307
308 acpi_status acpi_ut_release_mutex(acpi_mutex_handle mutex_id)
309 {
310         ACPI_FUNCTION_NAME(ut_release_mutex);
311
312         ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Thread %u releasing Mutex [%s]\n",
313                           (u32)acpi_os_get_thread_id(),
314                           acpi_ut_get_mutex_name(mutex_id)));
315
316         if (mutex_id > ACPI_MAX_MUTEX) {
317                 return (AE_BAD_PARAMETER);
318         }
319
320         /*
321          * Mutex must be acquired in order to release it!
322          */
323         if (acpi_gbl_mutex_info[mutex_id].thread_id == ACPI_MUTEX_NOT_ACQUIRED) {
324                 ACPI_ERROR((AE_INFO,
325                             "Mutex [0x%X] is not acquired, cannot release",
326                             mutex_id));
327
328                 return (AE_NOT_ACQUIRED);
329         }
330 #ifdef ACPI_MUTEX_DEBUG
331         {
332                 u32 i;
333                 /*
334                  * Mutex debug code, for internal debugging only.
335                  *
336                  * Deadlock prevention. Check if this thread owns any mutexes of value
337                  * greater than this one. If so, the thread has violated the mutex
338                  * ordering rule. This indicates a coding error somewhere in
339                  * the ACPI subsystem code.
340                  */
341                 for (i = mutex_id; i < ACPI_NUM_MUTEX; i++) {
342                         if (acpi_gbl_mutex_info[i].thread_id ==
343                             acpi_os_get_thread_id()) {
344                                 if (i == mutex_id) {
345                                         continue;
346                                 }
347
348                                 ACPI_ERROR((AE_INFO,
349                                             "Invalid release order: owns [%s], releasing [%s]",
350                                             acpi_ut_get_mutex_name(i),
351                                             acpi_ut_get_mutex_name(mutex_id)));
352
353                                 return (AE_RELEASE_DEADLOCK);
354                         }
355                 }
356         }
357 #endif
358
359         /* Mark unlocked FIRST */
360
361         acpi_gbl_mutex_info[mutex_id].thread_id = ACPI_MUTEX_NOT_ACQUIRED;
362
363         acpi_os_release_mutex(acpi_gbl_mutex_info[mutex_id].mutex);
364         return (AE_OK);
365 }