1/**************************************************************************
2 *
3 * Copyright (c) 2007-2009 VMware, Inc., Palo Alto, CA., USA
4 * All Rights Reserved.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sub license, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
13 *
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
16 * of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
21 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
22 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
23 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
24 * USE OR OTHER DEALINGS IN THE SOFTWARE.
25 *
26 **************************************************************************/
27/*
28 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
29 */
30/*
31 * Copyright (c) 2013 The FreeBSD Foundation
32 * All rights reserved.
33 *
34 * Portions of this software were developed by Konstantin Belousov
35 * <kib@FreeBSD.org> under sponsorship from the FreeBSD Foundation.
36 */
37
38#include <sys/cdefs.h>
39__FBSDID("$FreeBSD: stable/10/sys/dev/drm2/ttm/ttm_lock.c 259742 2013-12-22 21:18:21Z dumbbell $");
40
41#include <dev/drm2/ttm/ttm_lock.h>
42#include <dev/drm2/ttm/ttm_module.h>
43
44#define TTM_WRITE_LOCK_PENDING (1 << 0)
45#define TTM_VT_LOCK_PENDING (1 << 1)
46#define TTM_SUSPEND_LOCK_PENDING (1 << 2)
47#define TTM_VT_LOCK (1 << 3)
48#define TTM_SUSPEND_LOCK (1 << 4)
49
50void ttm_lock_init(struct ttm_lock *lock)
51{
52 mtx_init(&lock->lock, "ttmlk", NULL, MTX_DEF);
53 lock->rw = 0;
54 lock->flags = 0;
55 lock->kill_takers = false;
56 lock->signal = SIGKILL;
57}
58
59static void
60ttm_lock_send_sig(int signo)
61{
62 struct proc *p;
63
64 p = curproc; /* XXXKIB curthread ? */
65 PROC_LOCK(p);
66 kern_psignal(p, signo);
67 PROC_UNLOCK(p);
68}
69
70void ttm_read_unlock(struct ttm_lock *lock)
71{
72 mtx_lock(&lock->lock);
73 if (--lock->rw == 0)
74 wakeup(lock);
75 mtx_unlock(&lock->lock);
76}
77
78static bool __ttm_read_lock(struct ttm_lock *lock)
79{
80 bool locked = false;
81
82 if (unlikely(lock->kill_takers)) {
83 ttm_lock_send_sig(lock->signal);
84 return false;
85 }
86 if (lock->rw >= 0 && lock->flags == 0) {
87 ++lock->rw;
88 locked = true;
89 }
90 return locked;
91}
92
93int
94ttm_read_lock(struct ttm_lock *lock, bool interruptible)
95{
96 const char *wmsg;
97 int flags, ret;
98
99 ret = 0;
100 if (interruptible) {
101 flags = PCATCH;
102 wmsg = "ttmri";
103 } else {
104 flags = 0;
105 wmsg = "ttmr";
106 }
107 mtx_lock(&lock->lock);
108 while (!__ttm_read_lock(lock)) {
109 ret = msleep(lock, &lock->lock, flags, wmsg, 0);
110 if (ret == EINTR)
111 ret = ERESTARTSYS;
112 if (ret != 0)
113 break;
114 }
115 return (-ret);
116}
117
118static bool __ttm_read_trylock(struct ttm_lock *lock, bool *locked)
119{
120 bool block = true;
121
122 *locked = false;
123
124 if (unlikely(lock->kill_takers)) {
125 ttm_lock_send_sig(lock->signal);
126 return false;
127 }
128 if (lock->rw >= 0 && lock->flags == 0) {
129 ++lock->rw;
130 block = false;
131 *locked = true;
132 } else if (lock->flags == 0) {
133 block = false;
134 }
135
136 return !block;
137}
138
139int ttm_read_trylock(struct ttm_lock *lock, bool interruptible)
140{
141 const char *wmsg;
142 int flags, ret;
143 bool locked;
144
145 ret = 0;
146 if (interruptible) {
147 flags = PCATCH;
148 wmsg = "ttmrti";
149 } else {
150 flags = 0;
151 wmsg = "ttmrt";
152 }
153 mtx_lock(&lock->lock);
154 while (!__ttm_read_trylock(lock, &locked)) {
155 ret = msleep(lock, &lock->lock, flags, wmsg, 0);
156 if (ret == EINTR)
157 ret = ERESTARTSYS;
158 if (ret != 0)
159 break;
160 }
161 MPASS(!locked || ret == 0);
162 mtx_unlock(&lock->lock);
163
164 return (locked) ? 0 : -EBUSY;
165}
166
167void ttm_write_unlock(struct ttm_lock *lock)
168{
169 mtx_lock(&lock->lock);
170 lock->rw = 0;
171 wakeup(lock);
172 mtx_unlock(&lock->lock);
173}
174
175static bool __ttm_write_lock(struct ttm_lock *lock)
176{
177 bool locked = false;
178
179 if (unlikely(lock->kill_takers)) {
180 ttm_lock_send_sig(lock->signal);
181 return false;
182 }
183 if (lock->rw == 0 && ((lock->flags & ~TTM_WRITE_LOCK_PENDING) == 0)) {
184 lock->rw = -1;
185 lock->flags &= ~TTM_WRITE_LOCK_PENDING;
186 locked = true;
187 } else {
188 lock->flags |= TTM_WRITE_LOCK_PENDING;
189 }
190 return locked;
191}
192
193int
194ttm_write_lock(struct ttm_lock *lock, bool interruptible)
195{
196 const char *wmsg;
197 int flags, ret;
198
199 ret = 0;
200 if (interruptible) {
201 flags = PCATCH;
202 wmsg = "ttmwi";
203 } else {
204 flags = 0;
205 wmsg = "ttmw";
206 }
207 mtx_lock(&lock->lock);
208 /* XXXKIB: linux uses __ttm_read_lock for uninterruptible sleeps */
209 while (!__ttm_write_lock(lock)) {
210 ret = msleep(lock, &lock->lock, flags, wmsg, 0);
211 if (ret == EINTR)
212 ret = ERESTARTSYS;
213 if (interruptible && ret != 0) {
214 lock->flags &= ~TTM_WRITE_LOCK_PENDING;
215 wakeup(lock);
216 break;
217 }
218 }
219 mtx_unlock(&lock->lock);
220
221 return (-ret);
222}
223
224void ttm_write_lock_downgrade(struct ttm_lock *lock)
225{
226 mtx_lock(&lock->lock);
227 lock->rw = 1;
228 wakeup(lock);
229 mtx_unlock(&lock->lock);
230}
231
232static int __ttm_vt_unlock(struct ttm_lock *lock)
233{
234 int ret = 0;
235
236 mtx_lock(&lock->lock);
237 if (unlikely(!(lock->flags & TTM_VT_LOCK)))
238 ret = -EINVAL;
239 lock->flags &= ~TTM_VT_LOCK;
240 wakeup(lock);
241 mtx_unlock(&lock->lock);
242
243 return ret;
244}
245
246static void ttm_vt_lock_remove(struct ttm_base_object **p_base)
247{
248 struct ttm_base_object *base = *p_base;
249 struct ttm_lock *lock = container_of(base, struct ttm_lock, base);
250 int ret;
251
252 *p_base = NULL;
253 ret = __ttm_vt_unlock(lock);
254 MPASS(ret == 0);
255}
256
257static bool __ttm_vt_lock(struct ttm_lock *lock)
258{
259 bool locked = false;
260
261 if (lock->rw == 0) {
262 lock->flags &= ~TTM_VT_LOCK_PENDING;
263 lock->flags |= TTM_VT_LOCK;
264 locked = true;
265 } else {
266 lock->flags |= TTM_VT_LOCK_PENDING;
267 }
268 return locked;
269}
270
271int ttm_vt_lock(struct ttm_lock *lock,
272 bool interruptible,
273 struct ttm_object_file *tfile)
274{
275 const char *wmsg;
276 int flags, ret;
277
278 ret = 0;
279 if (interruptible) {
280 flags = PCATCH;
281 wmsg = "ttmwi";
282 } else {
283 flags = 0;
284 wmsg = "ttmw";
285 }
286 mtx_lock(&lock->lock);
287 while (!__ttm_vt_lock(lock)) {
288 ret = msleep(lock, &lock->lock, flags, wmsg, 0);
289 if (ret == EINTR)
290 ret = ERESTARTSYS;
291 if (interruptible && ret != 0) {
292 lock->flags &= ~TTM_VT_LOCK_PENDING;
293 wakeup(lock);
294 break;
295 }
296 }
297
298 /*
299 * Add a base-object, the destructor of which will
300 * make sure the lock is released if the client dies
301 * while holding it.
302 */
303
304 ret = ttm_base_object_init(tfile, &lock->base, false,
305 ttm_lock_type, &ttm_vt_lock_remove, NULL);
306 if (ret)
307 (void)__ttm_vt_unlock(lock);
308 else
309 lock->vt_holder = tfile;
310
311 return (-ret);
312}
313
314int ttm_vt_unlock(struct ttm_lock *lock)
315{
316 return ttm_ref_object_base_unref(lock->vt_holder,
317 lock->base.hash.key, TTM_REF_USAGE);
318}
319
320void ttm_suspend_unlock(struct ttm_lock *lock)
321{
322 mtx_lock(&lock->lock);
323 lock->flags &= ~TTM_SUSPEND_LOCK;
324 wakeup(lock);
325 mtx_unlock(&lock->lock);
326}
327
328static bool __ttm_suspend_lock(struct ttm_lock *lock)
329{
330 bool locked = false;
331
332 if (lock->rw == 0) {
333 lock->flags &= ~TTM_SUSPEND_LOCK_PENDING;
334 lock->flags |= TTM_SUSPEND_LOCK;
335 locked = true;
336 } else {
337 lock->flags |= TTM_SUSPEND_LOCK_PENDING;
338 }
339 return locked;
340}
341
342void ttm_suspend_lock(struct ttm_lock *lock)
343{
344 mtx_lock(&lock->lock);
345 while (!__ttm_suspend_lock(lock))
346 msleep(lock, &lock->lock, 0, "ttms", 0);
347 mtx_unlock(&lock->lock);
348}
2 *
3 * Copyright (c) 2007-2009 VMware, Inc., Palo Alto, CA., USA
4 * All Rights Reserved.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sub license, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
13 *
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
16 * of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
21 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
22 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
23 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
24 * USE OR OTHER DEALINGS IN THE SOFTWARE.
25 *
26 **************************************************************************/
27/*
28 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
29 */
30/*
31 * Copyright (c) 2013 The FreeBSD Foundation
32 * All rights reserved.
33 *
34 * Portions of this software were developed by Konstantin Belousov
35 * <kib@FreeBSD.org> under sponsorship from the FreeBSD Foundation.
36 */
37
38#include <sys/cdefs.h>
39__FBSDID("$FreeBSD: stable/10/sys/dev/drm2/ttm/ttm_lock.c 259742 2013-12-22 21:18:21Z dumbbell $");
40
41#include <dev/drm2/ttm/ttm_lock.h>
42#include <dev/drm2/ttm/ttm_module.h>
43
44#define TTM_WRITE_LOCK_PENDING (1 << 0)
45#define TTM_VT_LOCK_PENDING (1 << 1)
46#define TTM_SUSPEND_LOCK_PENDING (1 << 2)
47#define TTM_VT_LOCK (1 << 3)
48#define TTM_SUSPEND_LOCK (1 << 4)
49
50void ttm_lock_init(struct ttm_lock *lock)
51{
52 mtx_init(&lock->lock, "ttmlk", NULL, MTX_DEF);
53 lock->rw = 0;
54 lock->flags = 0;
55 lock->kill_takers = false;
56 lock->signal = SIGKILL;
57}
58
59static void
60ttm_lock_send_sig(int signo)
61{
62 struct proc *p;
63
64 p = curproc; /* XXXKIB curthread ? */
65 PROC_LOCK(p);
66 kern_psignal(p, signo);
67 PROC_UNLOCK(p);
68}
69
70void ttm_read_unlock(struct ttm_lock *lock)
71{
72 mtx_lock(&lock->lock);
73 if (--lock->rw == 0)
74 wakeup(lock);
75 mtx_unlock(&lock->lock);
76}
77
78static bool __ttm_read_lock(struct ttm_lock *lock)
79{
80 bool locked = false;
81
82 if (unlikely(lock->kill_takers)) {
83 ttm_lock_send_sig(lock->signal);
84 return false;
85 }
86 if (lock->rw >= 0 && lock->flags == 0) {
87 ++lock->rw;
88 locked = true;
89 }
90 return locked;
91}
92
93int
94ttm_read_lock(struct ttm_lock *lock, bool interruptible)
95{
96 const char *wmsg;
97 int flags, ret;
98
99 ret = 0;
100 if (interruptible) {
101 flags = PCATCH;
102 wmsg = "ttmri";
103 } else {
104 flags = 0;
105 wmsg = "ttmr";
106 }
107 mtx_lock(&lock->lock);
108 while (!__ttm_read_lock(lock)) {
109 ret = msleep(lock, &lock->lock, flags, wmsg, 0);
110 if (ret == EINTR)
111 ret = ERESTARTSYS;
112 if (ret != 0)
113 break;
114 }
115 return (-ret);
116}
117
118static bool __ttm_read_trylock(struct ttm_lock *lock, bool *locked)
119{
120 bool block = true;
121
122 *locked = false;
123
124 if (unlikely(lock->kill_takers)) {
125 ttm_lock_send_sig(lock->signal);
126 return false;
127 }
128 if (lock->rw >= 0 && lock->flags == 0) {
129 ++lock->rw;
130 block = false;
131 *locked = true;
132 } else if (lock->flags == 0) {
133 block = false;
134 }
135
136 return !block;
137}
138
139int ttm_read_trylock(struct ttm_lock *lock, bool interruptible)
140{
141 const char *wmsg;
142 int flags, ret;
143 bool locked;
144
145 ret = 0;
146 if (interruptible) {
147 flags = PCATCH;
148 wmsg = "ttmrti";
149 } else {
150 flags = 0;
151 wmsg = "ttmrt";
152 }
153 mtx_lock(&lock->lock);
154 while (!__ttm_read_trylock(lock, &locked)) {
155 ret = msleep(lock, &lock->lock, flags, wmsg, 0);
156 if (ret == EINTR)
157 ret = ERESTARTSYS;
158 if (ret != 0)
159 break;
160 }
161 MPASS(!locked || ret == 0);
162 mtx_unlock(&lock->lock);
163
164 return (locked) ? 0 : -EBUSY;
165}
166
167void ttm_write_unlock(struct ttm_lock *lock)
168{
169 mtx_lock(&lock->lock);
170 lock->rw = 0;
171 wakeup(lock);
172 mtx_unlock(&lock->lock);
173}
174
175static bool __ttm_write_lock(struct ttm_lock *lock)
176{
177 bool locked = false;
178
179 if (unlikely(lock->kill_takers)) {
180 ttm_lock_send_sig(lock->signal);
181 return false;
182 }
183 if (lock->rw == 0 && ((lock->flags & ~TTM_WRITE_LOCK_PENDING) == 0)) {
184 lock->rw = -1;
185 lock->flags &= ~TTM_WRITE_LOCK_PENDING;
186 locked = true;
187 } else {
188 lock->flags |= TTM_WRITE_LOCK_PENDING;
189 }
190 return locked;
191}
192
193int
194ttm_write_lock(struct ttm_lock *lock, bool interruptible)
195{
196 const char *wmsg;
197 int flags, ret;
198
199 ret = 0;
200 if (interruptible) {
201 flags = PCATCH;
202 wmsg = "ttmwi";
203 } else {
204 flags = 0;
205 wmsg = "ttmw";
206 }
207 mtx_lock(&lock->lock);
208 /* XXXKIB: linux uses __ttm_read_lock for uninterruptible sleeps */
209 while (!__ttm_write_lock(lock)) {
210 ret = msleep(lock, &lock->lock, flags, wmsg, 0);
211 if (ret == EINTR)
212 ret = ERESTARTSYS;
213 if (interruptible && ret != 0) {
214 lock->flags &= ~TTM_WRITE_LOCK_PENDING;
215 wakeup(lock);
216 break;
217 }
218 }
219 mtx_unlock(&lock->lock);
220
221 return (-ret);
222}
223
224void ttm_write_lock_downgrade(struct ttm_lock *lock)
225{
226 mtx_lock(&lock->lock);
227 lock->rw = 1;
228 wakeup(lock);
229 mtx_unlock(&lock->lock);
230}
231
232static int __ttm_vt_unlock(struct ttm_lock *lock)
233{
234 int ret = 0;
235
236 mtx_lock(&lock->lock);
237 if (unlikely(!(lock->flags & TTM_VT_LOCK)))
238 ret = -EINVAL;
239 lock->flags &= ~TTM_VT_LOCK;
240 wakeup(lock);
241 mtx_unlock(&lock->lock);
242
243 return ret;
244}
245
246static void ttm_vt_lock_remove(struct ttm_base_object **p_base)
247{
248 struct ttm_base_object *base = *p_base;
249 struct ttm_lock *lock = container_of(base, struct ttm_lock, base);
250 int ret;
251
252 *p_base = NULL;
253 ret = __ttm_vt_unlock(lock);
254 MPASS(ret == 0);
255}
256
257static bool __ttm_vt_lock(struct ttm_lock *lock)
258{
259 bool locked = false;
260
261 if (lock->rw == 0) {
262 lock->flags &= ~TTM_VT_LOCK_PENDING;
263 lock->flags |= TTM_VT_LOCK;
264 locked = true;
265 } else {
266 lock->flags |= TTM_VT_LOCK_PENDING;
267 }
268 return locked;
269}
270
271int ttm_vt_lock(struct ttm_lock *lock,
272 bool interruptible,
273 struct ttm_object_file *tfile)
274{
275 const char *wmsg;
276 int flags, ret;
277
278 ret = 0;
279 if (interruptible) {
280 flags = PCATCH;
281 wmsg = "ttmwi";
282 } else {
283 flags = 0;
284 wmsg = "ttmw";
285 }
286 mtx_lock(&lock->lock);
287 while (!__ttm_vt_lock(lock)) {
288 ret = msleep(lock, &lock->lock, flags, wmsg, 0);
289 if (ret == EINTR)
290 ret = ERESTARTSYS;
291 if (interruptible && ret != 0) {
292 lock->flags &= ~TTM_VT_LOCK_PENDING;
293 wakeup(lock);
294 break;
295 }
296 }
297
298 /*
299 * Add a base-object, the destructor of which will
300 * make sure the lock is released if the client dies
301 * while holding it.
302 */
303
304 ret = ttm_base_object_init(tfile, &lock->base, false,
305 ttm_lock_type, &ttm_vt_lock_remove, NULL);
306 if (ret)
307 (void)__ttm_vt_unlock(lock);
308 else
309 lock->vt_holder = tfile;
310
311 return (-ret);
312}
313
314int ttm_vt_unlock(struct ttm_lock *lock)
315{
316 return ttm_ref_object_base_unref(lock->vt_holder,
317 lock->base.hash.key, TTM_REF_USAGE);
318}
319
320void ttm_suspend_unlock(struct ttm_lock *lock)
321{
322 mtx_lock(&lock->lock);
323 lock->flags &= ~TTM_SUSPEND_LOCK;
324 wakeup(lock);
325 mtx_unlock(&lock->lock);
326}
327
328static bool __ttm_suspend_lock(struct ttm_lock *lock)
329{
330 bool locked = false;
331
332 if (lock->rw == 0) {
333 lock->flags &= ~TTM_SUSPEND_LOCK_PENDING;
334 lock->flags |= TTM_SUSPEND_LOCK;
335 locked = true;
336 } else {
337 lock->flags |= TTM_SUSPEND_LOCK_PENDING;
338 }
339 return locked;
340}
341
342void ttm_suspend_lock(struct ttm_lock *lock)
343{
344 mtx_lock(&lock->lock);
345 while (!__ttm_suspend_lock(lock))
346 msleep(lock, &lock->lock, 0, "ttms", 0);
347 mtx_unlock(&lock->lock);
348}