1 /*
2 * Copyright (C) 2007 Ben Skeggs.
3 * All Rights Reserved.
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining
6 * a copy of this software and associated documentation files (the
7 * "Software"), to deal in the Software without restriction, including
8 * without limitation the rights to use, copy, modify, merge, publish,
9 * distribute, sublicense, and/or sell copies of the Software, and to
10 * permit persons to whom the Software is furnished to do so, subject to
11 * the following conditions:
12 *
13 * The above copyright notice and this permission notice (including the
14 * next paragraph) shall be included in all copies or substantial
15 * portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
18 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
19 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
20 * IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
21 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
22 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
23 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
24 *
25 */
26
27 #include <drm/drmP.h>
28
29 #include <linux/ktime.h>
30 #include <linux/hrtimer.h>
31 #include <trace/events/fence.h>
32
33 #include <nvif/notify.h>
34 #include <nvif/event.h>
35
36 #include "nouveau_drm.h"
37 #include "nouveau_dma.h"
38 #include "nouveau_fence.h"
39
40 static const struct fence_ops nouveau_fence_ops_uevent;
41 static const struct fence_ops nouveau_fence_ops_legacy;
42
43 static inline struct nouveau_fence *
from_fence(struct fence * fence)44 from_fence(struct fence *fence)
45 {
46 return container_of(fence, struct nouveau_fence, base);
47 }
48
49 static inline struct nouveau_fence_chan *
nouveau_fctx(struct nouveau_fence * fence)50 nouveau_fctx(struct nouveau_fence *fence)
51 {
52 return container_of(fence->base.lock, struct nouveau_fence_chan, lock);
53 }
54
55 static int
nouveau_fence_signal(struct nouveau_fence * fence)56 nouveau_fence_signal(struct nouveau_fence *fence)
57 {
58 int drop = 0;
59
60 fence_signal_locked(&fence->base);
61 list_del(&fence->head);
62 rcu_assign_pointer(fence->channel, NULL);
63
64 if (test_bit(FENCE_FLAG_USER_BITS, &fence->base.flags)) {
65 struct nouveau_fence_chan *fctx = nouveau_fctx(fence);
66
67 if (!--fctx->notify_ref)
68 drop = 1;
69 }
70
71 fence_put(&fence->base);
72 return drop;
73 }
74
75 static struct nouveau_fence *
nouveau_local_fence(struct fence * fence,struct nouveau_drm * drm)76 nouveau_local_fence(struct fence *fence, struct nouveau_drm *drm) {
77 struct nouveau_fence_priv *priv = (void*)drm->fence;
78
79 if (fence->ops != &nouveau_fence_ops_legacy &&
80 fence->ops != &nouveau_fence_ops_uevent)
81 return NULL;
82
83 if (fence->context < priv->context_base ||
84 fence->context >= priv->context_base + priv->contexts)
85 return NULL;
86
87 return from_fence(fence);
88 }
89
90 void
nouveau_fence_context_del(struct nouveau_fence_chan * fctx)91 nouveau_fence_context_del(struct nouveau_fence_chan *fctx)
92 {
93 struct nouveau_fence *fence;
94
95 spin_lock_irq(&fctx->lock);
96 while (!list_empty(&fctx->pending)) {
97 fence = list_entry(fctx->pending.next, typeof(*fence), head);
98
99 if (nouveau_fence_signal(fence))
100 nvif_notify_put(&fctx->notify);
101 }
102 spin_unlock_irq(&fctx->lock);
103
104 nvif_notify_fini(&fctx->notify);
105 fctx->dead = 1;
106
107 /*
108 * Ensure that all accesses to fence->channel complete before freeing
109 * the channel.
110 */
111 synchronize_rcu();
112 }
113
114 static void
nouveau_fence_context_put(struct kref * fence_ref)115 nouveau_fence_context_put(struct kref *fence_ref)
116 {
117 kfree(container_of(fence_ref, struct nouveau_fence_chan, fence_ref));
118 }
119
120 void
nouveau_fence_context_free(struct nouveau_fence_chan * fctx)121 nouveau_fence_context_free(struct nouveau_fence_chan *fctx)
122 {
123 kref_put(&fctx->fence_ref, nouveau_fence_context_put);
124 }
125
126 static int
nouveau_fence_update(struct nouveau_channel * chan,struct nouveau_fence_chan * fctx)127 nouveau_fence_update(struct nouveau_channel *chan, struct nouveau_fence_chan *fctx)
128 {
129 struct nouveau_fence *fence;
130 int drop = 0;
131 u32 seq = fctx->read(chan);
132
133 while (!list_empty(&fctx->pending)) {
134 fence = list_entry(fctx->pending.next, typeof(*fence), head);
135
136 if ((int)(seq - fence->base.seqno) < 0)
137 break;
138
139 drop |= nouveau_fence_signal(fence);
140 }
141
142 return drop;
143 }
144
145 static int
nouveau_fence_wait_uevent_handler(struct nvif_notify * notify)146 nouveau_fence_wait_uevent_handler(struct nvif_notify *notify)
147 {
148 struct nouveau_fence_chan *fctx =
149 container_of(notify, typeof(*fctx), notify);
150 unsigned long flags;
151 int ret = NVIF_NOTIFY_KEEP;
152
153 spin_lock_irqsave(&fctx->lock, flags);
154 if (!list_empty(&fctx->pending)) {
155 struct nouveau_fence *fence;
156 struct nouveau_channel *chan;
157
158 fence = list_entry(fctx->pending.next, typeof(*fence), head);
159 chan = rcu_dereference_protected(fence->channel, lockdep_is_held(&fctx->lock));
160 if (nouveau_fence_update(chan, fctx))
161 ret = NVIF_NOTIFY_DROP;
162 }
163 spin_unlock_irqrestore(&fctx->lock, flags);
164
165 return ret;
166 }
167
168 void
nouveau_fence_context_new(struct nouveau_channel * chan,struct nouveau_fence_chan * fctx)169 nouveau_fence_context_new(struct nouveau_channel *chan, struct nouveau_fence_chan *fctx)
170 {
171 struct nouveau_fence_priv *priv = (void*)chan->drm->fence;
172 struct nouveau_cli *cli = (void *)chan->user.client;
173 int ret;
174
175 INIT_LIST_HEAD(&fctx->flip);
176 INIT_LIST_HEAD(&fctx->pending);
177 spin_lock_init(&fctx->lock);
178 fctx->context = priv->context_base + chan->chid;
179
180 if (chan == chan->drm->cechan)
181 strcpy(fctx->name, "copy engine channel");
182 else if (chan == chan->drm->channel)
183 strcpy(fctx->name, "generic kernel channel");
184 else
185 strcpy(fctx->name, nvxx_client(&cli->base)->name);
186
187 kref_init(&fctx->fence_ref);
188 if (!priv->uevent)
189 return;
190
191 ret = nvif_notify_init(&chan->user, nouveau_fence_wait_uevent_handler,
192 false, G82_CHANNEL_DMA_V0_NTFY_UEVENT,
193 &(struct nvif_notify_uevent_req) { },
194 sizeof(struct nvif_notify_uevent_req),
195 sizeof(struct nvif_notify_uevent_rep),
196 &fctx->notify);
197
198 WARN_ON(ret);
199 }
200
201 struct nouveau_fence_work {
202 struct work_struct work;
203 struct fence_cb cb;
204 void (*func)(void *);
205 void *data;
206 };
207
208 static void
nouveau_fence_work_handler(struct work_struct * kwork)209 nouveau_fence_work_handler(struct work_struct *kwork)
210 {
211 struct nouveau_fence_work *work = container_of(kwork, typeof(*work), work);
212 work->func(work->data);
213 kfree(work);
214 }
215
nouveau_fence_work_cb(struct fence * fence,struct fence_cb * cb)216 static void nouveau_fence_work_cb(struct fence *fence, struct fence_cb *cb)
217 {
218 struct nouveau_fence_work *work = container_of(cb, typeof(*work), cb);
219
220 schedule_work(&work->work);
221 }
222
223 void
nouveau_fence_work(struct fence * fence,void (* func)(void *),void * data)224 nouveau_fence_work(struct fence *fence,
225 void (*func)(void *), void *data)
226 {
227 struct nouveau_fence_work *work;
228
229 if (fence_is_signaled(fence))
230 goto err;
231
232 work = kmalloc(sizeof(*work), GFP_KERNEL);
233 if (!work) {
234 /*
235 * this might not be a nouveau fence any more,
236 * so force a lazy wait here
237 */
238 WARN_ON(nouveau_fence_wait((struct nouveau_fence *)fence,
239 true, false));
240 goto err;
241 }
242
243 INIT_WORK(&work->work, nouveau_fence_work_handler);
244 work->func = func;
245 work->data = data;
246
247 if (fence_add_callback(fence, &work->cb, nouveau_fence_work_cb) < 0)
248 goto err_free;
249 return;
250
251 err_free:
252 kfree(work);
253 err:
254 func(data);
255 }
256
257 int
nouveau_fence_emit(struct nouveau_fence * fence,struct nouveau_channel * chan)258 nouveau_fence_emit(struct nouveau_fence *fence, struct nouveau_channel *chan)
259 {
260 struct nouveau_fence_chan *fctx = chan->fence;
261 struct nouveau_fence_priv *priv = (void*)chan->drm->fence;
262 int ret;
263
264 fence->channel = chan;
265 fence->timeout = jiffies + (15 * HZ);
266
267 if (priv->uevent)
268 fence_init(&fence->base, &nouveau_fence_ops_uevent,
269 &fctx->lock, fctx->context, ++fctx->sequence);
270 else
271 fence_init(&fence->base, &nouveau_fence_ops_legacy,
272 &fctx->lock, fctx->context, ++fctx->sequence);
273 kref_get(&fctx->fence_ref);
274
275 trace_fence_emit(&fence->base);
276 ret = fctx->emit(fence);
277 if (!ret) {
278 fence_get(&fence->base);
279 spin_lock_irq(&fctx->lock);
280
281 if (nouveau_fence_update(chan, fctx))
282 nvif_notify_put(&fctx->notify);
283
284 list_add_tail(&fence->head, &fctx->pending);
285 spin_unlock_irq(&fctx->lock);
286 }
287
288 return ret;
289 }
290
291 bool
nouveau_fence_done(struct nouveau_fence * fence)292 nouveau_fence_done(struct nouveau_fence *fence)
293 {
294 if (fence->base.ops == &nouveau_fence_ops_legacy ||
295 fence->base.ops == &nouveau_fence_ops_uevent) {
296 struct nouveau_fence_chan *fctx = nouveau_fctx(fence);
297 struct nouveau_channel *chan;
298 unsigned long flags;
299
300 if (test_bit(FENCE_FLAG_SIGNALED_BIT, &fence->base.flags))
301 return true;
302
303 spin_lock_irqsave(&fctx->lock, flags);
304 chan = rcu_dereference_protected(fence->channel, lockdep_is_held(&fctx->lock));
305 if (chan && nouveau_fence_update(chan, fctx))
306 nvif_notify_put(&fctx->notify);
307 spin_unlock_irqrestore(&fctx->lock, flags);
308 }
309 return fence_is_signaled(&fence->base);
310 }
311
312 static long
nouveau_fence_wait_legacy(struct fence * f,bool intr,long wait)313 nouveau_fence_wait_legacy(struct fence *f, bool intr, long wait)
314 {
315 struct nouveau_fence *fence = from_fence(f);
316 unsigned long sleep_time = NSEC_PER_MSEC / 1000;
317 unsigned long t = jiffies, timeout = t + wait;
318
319 while (!nouveau_fence_done(fence)) {
320 ktime_t kt;
321
322 t = jiffies;
323
324 if (wait != MAX_SCHEDULE_TIMEOUT && time_after_eq(t, timeout)) {
325 __set_current_state(TASK_RUNNING);
326 return 0;
327 }
328
329 __set_current_state(intr ? TASK_INTERRUPTIBLE :
330 TASK_UNINTERRUPTIBLE);
331
332 kt = ktime_set(0, sleep_time);
333 schedule_hrtimeout(&kt, HRTIMER_MODE_REL);
334 sleep_time *= 2;
335 if (sleep_time > NSEC_PER_MSEC)
336 sleep_time = NSEC_PER_MSEC;
337
338 if (intr && signal_pending(current))
339 return -ERESTARTSYS;
340 }
341
342 __set_current_state(TASK_RUNNING);
343
344 return timeout - t;
345 }
346
347 static int
nouveau_fence_wait_busy(struct nouveau_fence * fence,bool intr)348 nouveau_fence_wait_busy(struct nouveau_fence *fence, bool intr)
349 {
350 int ret = 0;
351
352 while (!nouveau_fence_done(fence)) {
353 if (time_after_eq(jiffies, fence->timeout)) {
354 ret = -EBUSY;
355 break;
356 }
357
358 __set_current_state(intr ?
359 TASK_INTERRUPTIBLE :
360 TASK_UNINTERRUPTIBLE);
361
362 if (intr && signal_pending(current)) {
363 ret = -ERESTARTSYS;
364 break;
365 }
366 }
367
368 __set_current_state(TASK_RUNNING);
369 return ret;
370 }
371
372 int
nouveau_fence_wait(struct nouveau_fence * fence,bool lazy,bool intr)373 nouveau_fence_wait(struct nouveau_fence *fence, bool lazy, bool intr)
374 {
375 long ret;
376
377 if (!lazy)
378 return nouveau_fence_wait_busy(fence, intr);
379
380 ret = fence_wait_timeout(&fence->base, intr, 15 * HZ);
381 if (ret < 0)
382 return ret;
383 else if (!ret)
384 return -EBUSY;
385 else
386 return 0;
387 }
388
389 int
nouveau_fence_sync(struct nouveau_bo * nvbo,struct nouveau_channel * chan,bool exclusive,bool intr)390 nouveau_fence_sync(struct nouveau_bo *nvbo, struct nouveau_channel *chan, bool exclusive, bool intr)
391 {
392 struct nouveau_fence_chan *fctx = chan->fence;
393 struct fence *fence;
394 struct reservation_object *resv = nvbo->bo.resv;
395 struct reservation_object_list *fobj;
396 struct nouveau_fence *f;
397 int ret = 0, i;
398
399 if (!exclusive) {
400 ret = reservation_object_reserve_shared(resv);
401
402 if (ret)
403 return ret;
404 }
405
406 fobj = reservation_object_get_list(resv);
407 fence = reservation_object_get_excl(resv);
408
409 if (fence && (!exclusive || !fobj || !fobj->shared_count)) {
410 struct nouveau_channel *prev = NULL;
411 bool must_wait = true;
412
413 f = nouveau_local_fence(fence, chan->drm);
414 if (f) {
415 rcu_read_lock();
416 prev = rcu_dereference(f->channel);
417 if (prev && (prev == chan || fctx->sync(f, prev, chan) == 0))
418 must_wait = false;
419 rcu_read_unlock();
420 }
421
422 if (must_wait)
423 ret = fence_wait(fence, intr);
424
425 return ret;
426 }
427
428 if (!exclusive || !fobj)
429 return ret;
430
431 for (i = 0; i < fobj->shared_count && !ret; ++i) {
432 struct nouveau_channel *prev = NULL;
433 bool must_wait = true;
434
435 fence = rcu_dereference_protected(fobj->shared[i],
436 reservation_object_held(resv));
437
438 f = nouveau_local_fence(fence, chan->drm);
439 if (f) {
440 rcu_read_lock();
441 prev = rcu_dereference(f->channel);
442 if (prev && (prev == chan || fctx->sync(f, prev, chan) == 0))
443 must_wait = false;
444 rcu_read_unlock();
445 }
446
447 if (must_wait)
448 ret = fence_wait(fence, intr);
449 }
450
451 return ret;
452 }
453
454 void
nouveau_fence_unref(struct nouveau_fence ** pfence)455 nouveau_fence_unref(struct nouveau_fence **pfence)
456 {
457 if (*pfence)
458 fence_put(&(*pfence)->base);
459 *pfence = NULL;
460 }
461
462 int
nouveau_fence_new(struct nouveau_channel * chan,bool sysmem,struct nouveau_fence ** pfence)463 nouveau_fence_new(struct nouveau_channel *chan, bool sysmem,
464 struct nouveau_fence **pfence)
465 {
466 struct nouveau_fence *fence;
467 int ret = 0;
468
469 if (unlikely(!chan->fence))
470 return -ENODEV;
471
472 fence = kzalloc(sizeof(*fence), GFP_KERNEL);
473 if (!fence)
474 return -ENOMEM;
475
476 fence->sysmem = sysmem;
477
478 ret = nouveau_fence_emit(fence, chan);
479 if (ret)
480 nouveau_fence_unref(&fence);
481
482 *pfence = fence;
483 return ret;
484 }
485
nouveau_fence_get_get_driver_name(struct fence * fence)486 static const char *nouveau_fence_get_get_driver_name(struct fence *fence)
487 {
488 return "nouveau";
489 }
490
nouveau_fence_get_timeline_name(struct fence * f)491 static const char *nouveau_fence_get_timeline_name(struct fence *f)
492 {
493 struct nouveau_fence *fence = from_fence(f);
494 struct nouveau_fence_chan *fctx = nouveau_fctx(fence);
495
496 return !fctx->dead ? fctx->name : "dead channel";
497 }
498
499 /*
500 * In an ideal world, read would not assume the channel context is still alive.
501 * This function may be called from another device, running into free memory as a
502 * result. The drm node should still be there, so we can derive the index from
503 * the fence context.
504 */
nouveau_fence_is_signaled(struct fence * f)505 static bool nouveau_fence_is_signaled(struct fence *f)
506 {
507 struct nouveau_fence *fence = from_fence(f);
508 struct nouveau_fence_chan *fctx = nouveau_fctx(fence);
509 struct nouveau_channel *chan;
510 bool ret = false;
511
512 rcu_read_lock();
513 chan = rcu_dereference(fence->channel);
514 if (chan)
515 ret = (int)(fctx->read(chan) - fence->base.seqno) >= 0;
516 rcu_read_unlock();
517
518 return ret;
519 }
520
nouveau_fence_no_signaling(struct fence * f)521 static bool nouveau_fence_no_signaling(struct fence *f)
522 {
523 struct nouveau_fence *fence = from_fence(f);
524
525 /*
526 * caller should have a reference on the fence,
527 * else fence could get freed here
528 */
529 WARN_ON(atomic_read(&fence->base.refcount.refcount) <= 1);
530
531 /*
532 * This needs uevents to work correctly, but fence_add_callback relies on
533 * being able to enable signaling. It will still get signaled eventually,
534 * just not right away.
535 */
536 if (nouveau_fence_is_signaled(f)) {
537 list_del(&fence->head);
538
539 fence_put(&fence->base);
540 return false;
541 }
542
543 return true;
544 }
545
nouveau_fence_release(struct fence * f)546 static void nouveau_fence_release(struct fence *f)
547 {
548 struct nouveau_fence *fence = from_fence(f);
549 struct nouveau_fence_chan *fctx = nouveau_fctx(fence);
550
551 kref_put(&fctx->fence_ref, nouveau_fence_context_put);
552 fence_free(&fence->base);
553 }
554
555 static const struct fence_ops nouveau_fence_ops_legacy = {
556 .get_driver_name = nouveau_fence_get_get_driver_name,
557 .get_timeline_name = nouveau_fence_get_timeline_name,
558 .enable_signaling = nouveau_fence_no_signaling,
559 .signaled = nouveau_fence_is_signaled,
560 .wait = nouveau_fence_wait_legacy,
561 .release = nouveau_fence_release
562 };
563
nouveau_fence_enable_signaling(struct fence * f)564 static bool nouveau_fence_enable_signaling(struct fence *f)
565 {
566 struct nouveau_fence *fence = from_fence(f);
567 struct nouveau_fence_chan *fctx = nouveau_fctx(fence);
568 bool ret;
569
570 if (!fctx->notify_ref++)
571 nvif_notify_get(&fctx->notify);
572
573 ret = nouveau_fence_no_signaling(f);
574 if (ret)
575 set_bit(FENCE_FLAG_USER_BITS, &fence->base.flags);
576 else if (!--fctx->notify_ref)
577 nvif_notify_put(&fctx->notify);
578
579 return ret;
580 }
581
582 static const struct fence_ops nouveau_fence_ops_uevent = {
583 .get_driver_name = nouveau_fence_get_get_driver_name,
584 .get_timeline_name = nouveau_fence_get_timeline_name,
585 .enable_signaling = nouveau_fence_enable_signaling,
586 .signaled = nouveau_fence_is_signaled,
587 .wait = fence_default_wait,
588 .release = NULL
589 };
590