xref: /openbmc/linux/drivers/gpu/drm/drm_syncobj.c (revision 9659281c)
1 /*
2  * Copyright 2017 Red Hat
3  * Parts ported from amdgpu (fence wait code).
4  * Copyright 2016 Advanced Micro Devices, Inc.
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a
7  * copy of this software and associated documentation files (the "Software"),
8  * to deal in the Software without restriction, including without limitation
9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10  * and/or sell copies of the Software, and to permit persons to whom the
11  * Software is furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice (including the next
14  * paragraph) shall be included in all copies or substantial portions of the
15  * Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
22  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
23  * IN THE SOFTWARE.
24  *
25  * Authors:
26  *
27  */
28 
29 /**
30  * DOC: Overview
31  *
32  * DRM synchronisation objects (syncobj, see struct &drm_syncobj) provide a
33  * container for a synchronization primitive which can be used by userspace
34  * to explicitly synchronize GPU commands, can be shared between userspace
35  * processes, and can be shared between different DRM drivers.
36  * Their primary use-case is to implement Vulkan fences and semaphores.
37  * The syncobj userspace API provides ioctls for several operations:
38  *
39  *  - Creation and destruction of syncobjs
40  *  - Import and export of syncobjs to/from a syncobj file descriptor
41  *  - Import and export a syncobj's underlying fence to/from a sync file
42  *  - Reset a syncobj (set its fence to NULL)
43  *  - Signal a syncobj (set a trivially signaled fence)
44  *  - Wait for a syncobj's fence to appear and be signaled
45  *
46  * The syncobj userspace API also provides operations to manipulate a syncobj
47  * in terms of a timeline of struct &dma_fence_chain rather than a single
48  * struct &dma_fence, through the following operations:
49  *
50  *   - Signal a given point on the timeline
51  *   - Wait for a given point to appear and/or be signaled
52  *   - Import and export from/to a given point of a timeline
53  *
54  * At it's core, a syncobj is simply a wrapper around a pointer to a struct
55  * &dma_fence which may be NULL.
56  * When a syncobj is first created, its pointer is either NULL or a pointer
57  * to an already signaled fence depending on whether the
58  * &DRM_SYNCOBJ_CREATE_SIGNALED flag is passed to
59  * &DRM_IOCTL_SYNCOBJ_CREATE.
60  *
61  * If the syncobj is considered as a binary (its state is either signaled or
62  * unsignaled) primitive, when GPU work is enqueued in a DRM driver to signal
63  * the syncobj, the syncobj's fence is replaced with a fence which will be
64  * signaled by the completion of that work.
65  * If the syncobj is considered as a timeline primitive, when GPU work is
66  * enqueued in a DRM driver to signal the a given point of the syncobj, a new
67  * struct &dma_fence_chain pointing to the DRM driver's fence and also
68  * pointing to the previous fence that was in the syncobj. The new struct
69  * &dma_fence_chain fence replace the syncobj's fence and will be signaled by
70  * completion of the DRM driver's work and also any work associated with the
71  * fence previously in the syncobj.
72  *
73  * When GPU work which waits on a syncobj is enqueued in a DRM driver, at the
74  * time the work is enqueued, it waits on the syncobj's fence before
75  * submitting the work to hardware. That fence is either :
76  *
77  *    - The syncobj's current fence if the syncobj is considered as a binary
78  *      primitive.
79  *    - The struct &dma_fence associated with a given point if the syncobj is
80  *      considered as a timeline primitive.
81  *
82  * If the syncobj's fence is NULL or not present in the syncobj's timeline,
83  * the enqueue operation is expected to fail.
84  *
85  * With binary syncobj, all manipulation of the syncobjs's fence happens in
86  * terms of the current fence at the time the ioctl is called by userspace
87  * regardless of whether that operation is an immediate host-side operation
88  * (signal or reset) or or an operation which is enqueued in some driver
89  * queue. &DRM_IOCTL_SYNCOBJ_RESET and &DRM_IOCTL_SYNCOBJ_SIGNAL can be used
90  * to manipulate a syncobj from the host by resetting its pointer to NULL or
91  * setting its pointer to a fence which is already signaled.
92  *
93  * With a timeline syncobj, all manipulation of the synobj's fence happens in
94  * terms of a u64 value referring to point in the timeline. See
95  * dma_fence_chain_find_seqno() to see how a given point is found in the
96  * timeline.
97  *
98  * Note that applications should be careful to always use timeline set of
99  * ioctl() when dealing with syncobj considered as timeline. Using a binary
100  * set of ioctl() with a syncobj considered as timeline could result incorrect
101  * synchronization. The use of binary syncobj is supported through the
102  * timeline set of ioctl() by using a point value of 0, this will reproduce
103  * the behavior of the binary set of ioctl() (for example replace the
104  * syncobj's fence when signaling).
105  *
106  *
107  * Host-side wait on syncobjs
108  * --------------------------
109  *
110  * &DRM_IOCTL_SYNCOBJ_WAIT takes an array of syncobj handles and does a
111  * host-side wait on all of the syncobj fences simultaneously.
112  * If &DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL is set, the wait ioctl will wait on
113  * all of the syncobj fences to be signaled before it returns.
114  * Otherwise, it returns once at least one syncobj fence has been signaled
115  * and the index of a signaled fence is written back to the client.
116  *
117  * Unlike the enqueued GPU work dependencies which fail if they see a NULL
118  * fence in a syncobj, if &DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT is set,
119  * the host-side wait will first wait for the syncobj to receive a non-NULL
120  * fence and then wait on that fence.
121  * If &DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT is not set and any one of the
122  * syncobjs in the array has a NULL fence, -EINVAL will be returned.
123  * Assuming the syncobj starts off with a NULL fence, this allows a client
124  * to do a host wait in one thread (or process) which waits on GPU work
125  * submitted in another thread (or process) without having to manually
126  * synchronize between the two.
127  * This requirement is inherited from the Vulkan fence API.
128  *
129  * Similarly, &DRM_IOCTL_SYNCOBJ_TIMELINE_WAIT takes an array of syncobj
130  * handles as well as an array of u64 points and does a host-side wait on all
131  * of syncobj fences at the given points simultaneously.
132  *
133  * &DRM_IOCTL_SYNCOBJ_TIMELINE_WAIT also adds the ability to wait for a given
134  * fence to materialize on the timeline without waiting for the fence to be
135  * signaled by using the &DRM_SYNCOBJ_WAIT_FLAGS_WAIT_AVAILABLE flag. This
136  * requirement is inherited from the wait-before-signal behavior required by
137  * the Vulkan timeline semaphore API.
138  *
139  *
140  * Import/export of syncobjs
141  * -------------------------
142  *
143  * &DRM_IOCTL_SYNCOBJ_FD_TO_HANDLE and &DRM_IOCTL_SYNCOBJ_HANDLE_TO_FD
144  * provide two mechanisms for import/export of syncobjs.
145  *
146  * The first lets the client import or export an entire syncobj to a file
147  * descriptor.
148  * These fd's are opaque and have no other use case, except passing the
149  * syncobj between processes.
150  * All exported file descriptors and any syncobj handles created as a
151  * result of importing those file descriptors own a reference to the
152  * same underlying struct &drm_syncobj and the syncobj can be used
153  * persistently across all the processes with which it is shared.
154  * The syncobj is freed only once the last reference is dropped.
155  * Unlike dma-buf, importing a syncobj creates a new handle (with its own
156  * reference) for every import instead of de-duplicating.
157  * The primary use-case of this persistent import/export is for shared
158  * Vulkan fences and semaphores.
159  *
160  * The second import/export mechanism, which is indicated by
161  * &DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE or
162  * &DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE lets the client
163  * import/export the syncobj's current fence from/to a &sync_file.
164  * When a syncobj is exported to a sync file, that sync file wraps the
165  * sycnobj's fence at the time of export and any later signal or reset
166  * operations on the syncobj will not affect the exported sync file.
167  * When a sync file is imported into a syncobj, the syncobj's fence is set
168  * to the fence wrapped by that sync file.
169  * Because sync files are immutable, resetting or signaling the syncobj
170  * will not affect any sync files whose fences have been imported into the
171  * syncobj.
172  *
173  *
174  * Import/export of timeline points in timeline syncobjs
175  * -----------------------------------------------------
176  *
177  * &DRM_IOCTL_SYNCOBJ_TRANSFER provides a mechanism to transfer a struct
178  * &dma_fence_chain of a syncobj at a given u64 point to another u64 point
179  * into another syncobj.
180  *
181  * Note that if you want to transfer a struct &dma_fence_chain from a given
182  * point on a timeline syncobj from/into a binary syncobj, you can use the
183  * point 0 to mean take/replace the fence in the syncobj.
184  */
185 
186 #include <linux/anon_inodes.h>
187 #include <linux/file.h>
188 #include <linux/fs.h>
189 #include <linux/sched/signal.h>
190 #include <linux/sync_file.h>
191 #include <linux/uaccess.h>
192 
193 #include <drm/drm.h>
194 #include <drm/drm_drv.h>
195 #include <drm/drm_file.h>
196 #include <drm/drm_gem.h>
197 #include <drm/drm_print.h>
198 #include <drm/drm_syncobj.h>
199 #include <drm/drm_utils.h>
200 
201 #include "drm_internal.h"
202 
203 struct syncobj_wait_entry {
204 	struct list_head node;
205 	struct task_struct *task;
206 	struct dma_fence *fence;
207 	struct dma_fence_cb fence_cb;
208 	u64    point;
209 };
210 
211 static void syncobj_wait_syncobj_func(struct drm_syncobj *syncobj,
212 				      struct syncobj_wait_entry *wait);
213 
214 /**
215  * drm_syncobj_find - lookup and reference a sync object.
216  * @file_private: drm file private pointer
217  * @handle: sync object handle to lookup.
218  *
219  * Returns a reference to the syncobj pointed to by handle or NULL. The
220  * reference must be released by calling drm_syncobj_put().
221  */
222 struct drm_syncobj *drm_syncobj_find(struct drm_file *file_private,
223 				     u32 handle)
224 {
225 	struct drm_syncobj *syncobj;
226 
227 	spin_lock(&file_private->syncobj_table_lock);
228 
229 	/* Check if we currently have a reference on the object */
230 	syncobj = idr_find(&file_private->syncobj_idr, handle);
231 	if (syncobj)
232 		drm_syncobj_get(syncobj);
233 
234 	spin_unlock(&file_private->syncobj_table_lock);
235 
236 	return syncobj;
237 }
238 EXPORT_SYMBOL(drm_syncobj_find);
239 
240 static void drm_syncobj_fence_add_wait(struct drm_syncobj *syncobj,
241 				       struct syncobj_wait_entry *wait)
242 {
243 	struct dma_fence *fence;
244 
245 	if (wait->fence)
246 		return;
247 
248 	spin_lock(&syncobj->lock);
249 	/* We've already tried once to get a fence and failed.  Now that we
250 	 * have the lock, try one more time just to be sure we don't add a
251 	 * callback when a fence has already been set.
252 	 */
253 	fence = dma_fence_get(rcu_dereference_protected(syncobj->fence, 1));
254 	if (!fence || dma_fence_chain_find_seqno(&fence, wait->point)) {
255 		dma_fence_put(fence);
256 		list_add_tail(&wait->node, &syncobj->cb_list);
257 	} else if (!fence) {
258 		wait->fence = dma_fence_get_stub();
259 	} else {
260 		wait->fence = fence;
261 	}
262 	spin_unlock(&syncobj->lock);
263 }
264 
265 static void drm_syncobj_remove_wait(struct drm_syncobj *syncobj,
266 				    struct syncobj_wait_entry *wait)
267 {
268 	if (!wait->node.next)
269 		return;
270 
271 	spin_lock(&syncobj->lock);
272 	list_del_init(&wait->node);
273 	spin_unlock(&syncobj->lock);
274 }
275 
276 /**
277  * drm_syncobj_add_point - add new timeline point to the syncobj
278  * @syncobj: sync object to add timeline point do
279  * @chain: chain node to use to add the point
280  * @fence: fence to encapsulate in the chain node
281  * @point: sequence number to use for the point
282  *
283  * Add the chain node as new timeline point to the syncobj.
284  */
285 void drm_syncobj_add_point(struct drm_syncobj *syncobj,
286 			   struct dma_fence_chain *chain,
287 			   struct dma_fence *fence,
288 			   uint64_t point)
289 {
290 	struct syncobj_wait_entry *cur, *tmp;
291 	struct dma_fence *prev;
292 
293 	dma_fence_get(fence);
294 
295 	spin_lock(&syncobj->lock);
296 
297 	prev = drm_syncobj_fence_get(syncobj);
298 	/* You are adding an unorder point to timeline, which could cause payload returned from query_ioctl is 0! */
299 	if (prev && prev->seqno >= point)
300 		DRM_DEBUG("You are adding an unorder point to timeline!\n");
301 	dma_fence_chain_init(chain, prev, fence, point);
302 	rcu_assign_pointer(syncobj->fence, &chain->base);
303 
304 	list_for_each_entry_safe(cur, tmp, &syncobj->cb_list, node)
305 		syncobj_wait_syncobj_func(syncobj, cur);
306 	spin_unlock(&syncobj->lock);
307 
308 	/* Walk the chain once to trigger garbage collection */
309 	dma_fence_chain_for_each(fence, prev);
310 	dma_fence_put(prev);
311 }
312 EXPORT_SYMBOL(drm_syncobj_add_point);
313 
314 /**
315  * drm_syncobj_replace_fence - replace fence in a sync object.
316  * @syncobj: Sync object to replace fence in
317  * @fence: fence to install in sync file.
318  *
319  * This replaces the fence on a sync object.
320  */
321 void drm_syncobj_replace_fence(struct drm_syncobj *syncobj,
322 			       struct dma_fence *fence)
323 {
324 	struct dma_fence *old_fence;
325 	struct syncobj_wait_entry *cur, *tmp;
326 
327 	if (fence)
328 		dma_fence_get(fence);
329 
330 	spin_lock(&syncobj->lock);
331 
332 	old_fence = rcu_dereference_protected(syncobj->fence,
333 					      lockdep_is_held(&syncobj->lock));
334 	rcu_assign_pointer(syncobj->fence, fence);
335 
336 	if (fence != old_fence) {
337 		list_for_each_entry_safe(cur, tmp, &syncobj->cb_list, node)
338 			syncobj_wait_syncobj_func(syncobj, cur);
339 	}
340 
341 	spin_unlock(&syncobj->lock);
342 
343 	dma_fence_put(old_fence);
344 }
345 EXPORT_SYMBOL(drm_syncobj_replace_fence);
346 
347 /**
348  * drm_syncobj_assign_null_handle - assign a stub fence to the sync object
349  * @syncobj: sync object to assign the fence on
350  *
351  * Assign a already signaled stub fence to the sync object.
352  */
353 static int drm_syncobj_assign_null_handle(struct drm_syncobj *syncobj)
354 {
355 	struct dma_fence *fence = dma_fence_allocate_private_stub();
356 
357 	if (IS_ERR(fence))
358 		return PTR_ERR(fence);
359 
360 	drm_syncobj_replace_fence(syncobj, fence);
361 	dma_fence_put(fence);
362 	return 0;
363 }
364 
365 /* 5s default for wait submission */
366 #define DRM_SYNCOBJ_WAIT_FOR_SUBMIT_TIMEOUT 5000000000ULL
367 /**
368  * drm_syncobj_find_fence - lookup and reference the fence in a sync object
369  * @file_private: drm file private pointer
370  * @handle: sync object handle to lookup.
371  * @point: timeline point
372  * @flags: DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT or not
373  * @fence: out parameter for the fence
374  *
375  * This is just a convenience function that combines drm_syncobj_find() and
376  * drm_syncobj_fence_get().
377  *
378  * Returns 0 on success or a negative error value on failure. On success @fence
379  * contains a reference to the fence, which must be released by calling
380  * dma_fence_put().
381  */
382 int drm_syncobj_find_fence(struct drm_file *file_private,
383 			   u32 handle, u64 point, u64 flags,
384 			   struct dma_fence **fence)
385 {
386 	struct drm_syncobj *syncobj = drm_syncobj_find(file_private, handle);
387 	struct syncobj_wait_entry wait;
388 	u64 timeout = nsecs_to_jiffies64(DRM_SYNCOBJ_WAIT_FOR_SUBMIT_TIMEOUT);
389 	int ret;
390 
391 	if (!syncobj)
392 		return -ENOENT;
393 
394 	/* Waiting for userspace with locks help is illegal cause that can
395 	 * trivial deadlock with page faults for example. Make lockdep complain
396 	 * about it early on.
397 	 */
398 	if (flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT) {
399 		might_sleep();
400 		lockdep_assert_none_held_once();
401 	}
402 
403 	*fence = drm_syncobj_fence_get(syncobj);
404 
405 	if (*fence) {
406 		ret = dma_fence_chain_find_seqno(fence, point);
407 		if (!ret)
408 			goto out;
409 		dma_fence_put(*fence);
410 	} else {
411 		ret = -EINVAL;
412 	}
413 
414 	if (!(flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT))
415 		goto out;
416 
417 	memset(&wait, 0, sizeof(wait));
418 	wait.task = current;
419 	wait.point = point;
420 	drm_syncobj_fence_add_wait(syncobj, &wait);
421 
422 	do {
423 		set_current_state(TASK_INTERRUPTIBLE);
424 		if (wait.fence) {
425 			ret = 0;
426 			break;
427 		}
428                 if (timeout == 0) {
429                         ret = -ETIME;
430                         break;
431                 }
432 
433 		if (signal_pending(current)) {
434 			ret = -ERESTARTSYS;
435 			break;
436 		}
437 
438                 timeout = schedule_timeout(timeout);
439 	} while (1);
440 
441 	__set_current_state(TASK_RUNNING);
442 	*fence = wait.fence;
443 
444 	if (wait.node.next)
445 		drm_syncobj_remove_wait(syncobj, &wait);
446 
447 out:
448 	drm_syncobj_put(syncobj);
449 
450 	return ret;
451 }
452 EXPORT_SYMBOL(drm_syncobj_find_fence);
453 
454 /**
455  * drm_syncobj_free - free a sync object.
456  * @kref: kref to free.
457  *
458  * Only to be called from kref_put in drm_syncobj_put.
459  */
460 void drm_syncobj_free(struct kref *kref)
461 {
462 	struct drm_syncobj *syncobj = container_of(kref,
463 						   struct drm_syncobj,
464 						   refcount);
465 	drm_syncobj_replace_fence(syncobj, NULL);
466 	kfree(syncobj);
467 }
468 EXPORT_SYMBOL(drm_syncobj_free);
469 
470 /**
471  * drm_syncobj_create - create a new syncobj
472  * @out_syncobj: returned syncobj
473  * @flags: DRM_SYNCOBJ_* flags
474  * @fence: if non-NULL, the syncobj will represent this fence
475  *
476  * This is the first function to create a sync object. After creating, drivers
477  * probably want to make it available to userspace, either through
478  * drm_syncobj_get_handle() or drm_syncobj_get_fd().
479  *
480  * Returns 0 on success or a negative error value on failure.
481  */
482 int drm_syncobj_create(struct drm_syncobj **out_syncobj, uint32_t flags,
483 		       struct dma_fence *fence)
484 {
485 	int ret;
486 	struct drm_syncobj *syncobj;
487 
488 	syncobj = kzalloc(sizeof(struct drm_syncobj), GFP_KERNEL);
489 	if (!syncobj)
490 		return -ENOMEM;
491 
492 	kref_init(&syncobj->refcount);
493 	INIT_LIST_HEAD(&syncobj->cb_list);
494 	spin_lock_init(&syncobj->lock);
495 
496 	if (flags & DRM_SYNCOBJ_CREATE_SIGNALED) {
497 		ret = drm_syncobj_assign_null_handle(syncobj);
498 		if (ret < 0) {
499 			drm_syncobj_put(syncobj);
500 			return ret;
501 		}
502 	}
503 
504 	if (fence)
505 		drm_syncobj_replace_fence(syncobj, fence);
506 
507 	*out_syncobj = syncobj;
508 	return 0;
509 }
510 EXPORT_SYMBOL(drm_syncobj_create);
511 
512 /**
513  * drm_syncobj_get_handle - get a handle from a syncobj
514  * @file_private: drm file private pointer
515  * @syncobj: Sync object to export
516  * @handle: out parameter with the new handle
517  *
518  * Exports a sync object created with drm_syncobj_create() as a handle on
519  * @file_private to userspace.
520  *
521  * Returns 0 on success or a negative error value on failure.
522  */
523 int drm_syncobj_get_handle(struct drm_file *file_private,
524 			   struct drm_syncobj *syncobj, u32 *handle)
525 {
526 	int ret;
527 
528 	/* take a reference to put in the idr */
529 	drm_syncobj_get(syncobj);
530 
531 	idr_preload(GFP_KERNEL);
532 	spin_lock(&file_private->syncobj_table_lock);
533 	ret = idr_alloc(&file_private->syncobj_idr, syncobj, 1, 0, GFP_NOWAIT);
534 	spin_unlock(&file_private->syncobj_table_lock);
535 
536 	idr_preload_end();
537 
538 	if (ret < 0) {
539 		drm_syncobj_put(syncobj);
540 		return ret;
541 	}
542 
543 	*handle = ret;
544 	return 0;
545 }
546 EXPORT_SYMBOL(drm_syncobj_get_handle);
547 
548 static int drm_syncobj_create_as_handle(struct drm_file *file_private,
549 					u32 *handle, uint32_t flags)
550 {
551 	int ret;
552 	struct drm_syncobj *syncobj;
553 
554 	ret = drm_syncobj_create(&syncobj, flags, NULL);
555 	if (ret)
556 		return ret;
557 
558 	ret = drm_syncobj_get_handle(file_private, syncobj, handle);
559 	drm_syncobj_put(syncobj);
560 	return ret;
561 }
562 
563 static int drm_syncobj_destroy(struct drm_file *file_private,
564 			       u32 handle)
565 {
566 	struct drm_syncobj *syncobj;
567 
568 	spin_lock(&file_private->syncobj_table_lock);
569 	syncobj = idr_remove(&file_private->syncobj_idr, handle);
570 	spin_unlock(&file_private->syncobj_table_lock);
571 
572 	if (!syncobj)
573 		return -EINVAL;
574 
575 	drm_syncobj_put(syncobj);
576 	return 0;
577 }
578 
579 static int drm_syncobj_file_release(struct inode *inode, struct file *file)
580 {
581 	struct drm_syncobj *syncobj = file->private_data;
582 
583 	drm_syncobj_put(syncobj);
584 	return 0;
585 }
586 
587 static const struct file_operations drm_syncobj_file_fops = {
588 	.release = drm_syncobj_file_release,
589 };
590 
591 /**
592  * drm_syncobj_get_fd - get a file descriptor from a syncobj
593  * @syncobj: Sync object to export
594  * @p_fd: out parameter with the new file descriptor
595  *
596  * Exports a sync object created with drm_syncobj_create() as a file descriptor.
597  *
598  * Returns 0 on success or a negative error value on failure.
599  */
600 int drm_syncobj_get_fd(struct drm_syncobj *syncobj, int *p_fd)
601 {
602 	struct file *file;
603 	int fd;
604 
605 	fd = get_unused_fd_flags(O_CLOEXEC);
606 	if (fd < 0)
607 		return fd;
608 
609 	file = anon_inode_getfile("syncobj_file",
610 				  &drm_syncobj_file_fops,
611 				  syncobj, 0);
612 	if (IS_ERR(file)) {
613 		put_unused_fd(fd);
614 		return PTR_ERR(file);
615 	}
616 
617 	drm_syncobj_get(syncobj);
618 	fd_install(fd, file);
619 
620 	*p_fd = fd;
621 	return 0;
622 }
623 EXPORT_SYMBOL(drm_syncobj_get_fd);
624 
625 static int drm_syncobj_handle_to_fd(struct drm_file *file_private,
626 				    u32 handle, int *p_fd)
627 {
628 	struct drm_syncobj *syncobj = drm_syncobj_find(file_private, handle);
629 	int ret;
630 
631 	if (!syncobj)
632 		return -EINVAL;
633 
634 	ret = drm_syncobj_get_fd(syncobj, p_fd);
635 	drm_syncobj_put(syncobj);
636 	return ret;
637 }
638 
639 static int drm_syncobj_fd_to_handle(struct drm_file *file_private,
640 				    int fd, u32 *handle)
641 {
642 	struct drm_syncobj *syncobj;
643 	struct fd f = fdget(fd);
644 	int ret;
645 
646 	if (!f.file)
647 		return -EINVAL;
648 
649 	if (f.file->f_op != &drm_syncobj_file_fops) {
650 		fdput(f);
651 		return -EINVAL;
652 	}
653 
654 	/* take a reference to put in the idr */
655 	syncobj = f.file->private_data;
656 	drm_syncobj_get(syncobj);
657 
658 	idr_preload(GFP_KERNEL);
659 	spin_lock(&file_private->syncobj_table_lock);
660 	ret = idr_alloc(&file_private->syncobj_idr, syncobj, 1, 0, GFP_NOWAIT);
661 	spin_unlock(&file_private->syncobj_table_lock);
662 	idr_preload_end();
663 
664 	if (ret > 0) {
665 		*handle = ret;
666 		ret = 0;
667 	} else
668 		drm_syncobj_put(syncobj);
669 
670 	fdput(f);
671 	return ret;
672 }
673 
674 static int drm_syncobj_import_sync_file_fence(struct drm_file *file_private,
675 					      int fd, int handle)
676 {
677 	struct dma_fence *fence = sync_file_get_fence(fd);
678 	struct drm_syncobj *syncobj;
679 
680 	if (!fence)
681 		return -EINVAL;
682 
683 	syncobj = drm_syncobj_find(file_private, handle);
684 	if (!syncobj) {
685 		dma_fence_put(fence);
686 		return -ENOENT;
687 	}
688 
689 	drm_syncobj_replace_fence(syncobj, fence);
690 	dma_fence_put(fence);
691 	drm_syncobj_put(syncobj);
692 	return 0;
693 }
694 
695 static int drm_syncobj_export_sync_file(struct drm_file *file_private,
696 					int handle, int *p_fd)
697 {
698 	int ret;
699 	struct dma_fence *fence;
700 	struct sync_file *sync_file;
701 	int fd = get_unused_fd_flags(O_CLOEXEC);
702 
703 	if (fd < 0)
704 		return fd;
705 
706 	ret = drm_syncobj_find_fence(file_private, handle, 0, 0, &fence);
707 	if (ret)
708 		goto err_put_fd;
709 
710 	sync_file = sync_file_create(fence);
711 
712 	dma_fence_put(fence);
713 
714 	if (!sync_file) {
715 		ret = -EINVAL;
716 		goto err_put_fd;
717 	}
718 
719 	fd_install(fd, sync_file->file);
720 
721 	*p_fd = fd;
722 	return 0;
723 err_put_fd:
724 	put_unused_fd(fd);
725 	return ret;
726 }
727 /**
728  * drm_syncobj_open - initalizes syncobj file-private structures at devnode open time
729  * @file_private: drm file-private structure to set up
730  *
731  * Called at device open time, sets up the structure for handling refcounting
732  * of sync objects.
733  */
734 void
735 drm_syncobj_open(struct drm_file *file_private)
736 {
737 	idr_init_base(&file_private->syncobj_idr, 1);
738 	spin_lock_init(&file_private->syncobj_table_lock);
739 }
740 
741 static int
742 drm_syncobj_release_handle(int id, void *ptr, void *data)
743 {
744 	struct drm_syncobj *syncobj = ptr;
745 
746 	drm_syncobj_put(syncobj);
747 	return 0;
748 }
749 
750 /**
751  * drm_syncobj_release - release file-private sync object resources
752  * @file_private: drm file-private structure to clean up
753  *
754  * Called at close time when the filp is going away.
755  *
756  * Releases any remaining references on objects by this filp.
757  */
758 void
759 drm_syncobj_release(struct drm_file *file_private)
760 {
761 	idr_for_each(&file_private->syncobj_idr,
762 		     &drm_syncobj_release_handle, file_private);
763 	idr_destroy(&file_private->syncobj_idr);
764 }
765 
766 int
767 drm_syncobj_create_ioctl(struct drm_device *dev, void *data,
768 			 struct drm_file *file_private)
769 {
770 	struct drm_syncobj_create *args = data;
771 
772 	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
773 		return -EOPNOTSUPP;
774 
775 	/* no valid flags yet */
776 	if (args->flags & ~DRM_SYNCOBJ_CREATE_SIGNALED)
777 		return -EINVAL;
778 
779 	return drm_syncobj_create_as_handle(file_private,
780 					    &args->handle, args->flags);
781 }
782 
783 int
784 drm_syncobj_destroy_ioctl(struct drm_device *dev, void *data,
785 			  struct drm_file *file_private)
786 {
787 	struct drm_syncobj_destroy *args = data;
788 
789 	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
790 		return -EOPNOTSUPP;
791 
792 	/* make sure padding is empty */
793 	if (args->pad)
794 		return -EINVAL;
795 	return drm_syncobj_destroy(file_private, args->handle);
796 }
797 
798 int
799 drm_syncobj_handle_to_fd_ioctl(struct drm_device *dev, void *data,
800 				   struct drm_file *file_private)
801 {
802 	struct drm_syncobj_handle *args = data;
803 
804 	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
805 		return -EOPNOTSUPP;
806 
807 	if (args->pad)
808 		return -EINVAL;
809 
810 	if (args->flags != 0 &&
811 	    args->flags != DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE)
812 		return -EINVAL;
813 
814 	if (args->flags & DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE)
815 		return drm_syncobj_export_sync_file(file_private, args->handle,
816 						    &args->fd);
817 
818 	return drm_syncobj_handle_to_fd(file_private, args->handle,
819 					&args->fd);
820 }
821 
822 int
823 drm_syncobj_fd_to_handle_ioctl(struct drm_device *dev, void *data,
824 				   struct drm_file *file_private)
825 {
826 	struct drm_syncobj_handle *args = data;
827 
828 	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
829 		return -EOPNOTSUPP;
830 
831 	if (args->pad)
832 		return -EINVAL;
833 
834 	if (args->flags != 0 &&
835 	    args->flags != DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE)
836 		return -EINVAL;
837 
838 	if (args->flags & DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE)
839 		return drm_syncobj_import_sync_file_fence(file_private,
840 							  args->fd,
841 							  args->handle);
842 
843 	return drm_syncobj_fd_to_handle(file_private, args->fd,
844 					&args->handle);
845 }
846 
847 static int drm_syncobj_transfer_to_timeline(struct drm_file *file_private,
848 					    struct drm_syncobj_transfer *args)
849 {
850 	struct drm_syncobj *timeline_syncobj = NULL;
851 	struct dma_fence *fence;
852 	struct dma_fence_chain *chain;
853 	int ret;
854 
855 	timeline_syncobj = drm_syncobj_find(file_private, args->dst_handle);
856 	if (!timeline_syncobj) {
857 		return -ENOENT;
858 	}
859 	ret = drm_syncobj_find_fence(file_private, args->src_handle,
860 				     args->src_point, args->flags,
861 				     &fence);
862 	if (ret)
863 		goto err;
864 	chain = kzalloc(sizeof(struct dma_fence_chain), GFP_KERNEL);
865 	if (!chain) {
866 		ret = -ENOMEM;
867 		goto err1;
868 	}
869 	drm_syncobj_add_point(timeline_syncobj, chain, fence, args->dst_point);
870 err1:
871 	dma_fence_put(fence);
872 err:
873 	drm_syncobj_put(timeline_syncobj);
874 
875 	return ret;
876 }
877 
878 static int
879 drm_syncobj_transfer_to_binary(struct drm_file *file_private,
880 			       struct drm_syncobj_transfer *args)
881 {
882 	struct drm_syncobj *binary_syncobj = NULL;
883 	struct dma_fence *fence;
884 	int ret;
885 
886 	binary_syncobj = drm_syncobj_find(file_private, args->dst_handle);
887 	if (!binary_syncobj)
888 		return -ENOENT;
889 	ret = drm_syncobj_find_fence(file_private, args->src_handle,
890 				     args->src_point, args->flags, &fence);
891 	if (ret)
892 		goto err;
893 	drm_syncobj_replace_fence(binary_syncobj, fence);
894 	dma_fence_put(fence);
895 err:
896 	drm_syncobj_put(binary_syncobj);
897 
898 	return ret;
899 }
900 int
901 drm_syncobj_transfer_ioctl(struct drm_device *dev, void *data,
902 			   struct drm_file *file_private)
903 {
904 	struct drm_syncobj_transfer *args = data;
905 	int ret;
906 
907 	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE))
908 		return -EOPNOTSUPP;
909 
910 	if (args->pad)
911 		return -EINVAL;
912 
913 	if (args->dst_point)
914 		ret = drm_syncobj_transfer_to_timeline(file_private, args);
915 	else
916 		ret = drm_syncobj_transfer_to_binary(file_private, args);
917 
918 	return ret;
919 }
920 
921 static void syncobj_wait_fence_func(struct dma_fence *fence,
922 				    struct dma_fence_cb *cb)
923 {
924 	struct syncobj_wait_entry *wait =
925 		container_of(cb, struct syncobj_wait_entry, fence_cb);
926 
927 	wake_up_process(wait->task);
928 }
929 
930 static void syncobj_wait_syncobj_func(struct drm_syncobj *syncobj,
931 				      struct syncobj_wait_entry *wait)
932 {
933 	struct dma_fence *fence;
934 
935 	/* This happens inside the syncobj lock */
936 	fence = rcu_dereference_protected(syncobj->fence,
937 					  lockdep_is_held(&syncobj->lock));
938 	dma_fence_get(fence);
939 	if (!fence || dma_fence_chain_find_seqno(&fence, wait->point)) {
940 		dma_fence_put(fence);
941 		return;
942 	} else if (!fence) {
943 		wait->fence = dma_fence_get_stub();
944 	} else {
945 		wait->fence = fence;
946 	}
947 
948 	wake_up_process(wait->task);
949 	list_del_init(&wait->node);
950 }
951 
952 static signed long drm_syncobj_array_wait_timeout(struct drm_syncobj **syncobjs,
953 						  void __user *user_points,
954 						  uint32_t count,
955 						  uint32_t flags,
956 						  signed long timeout,
957 						  uint32_t *idx)
958 {
959 	struct syncobj_wait_entry *entries;
960 	struct dma_fence *fence;
961 	uint64_t *points;
962 	uint32_t signaled_count, i;
963 
964 	if (flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT)
965 		lockdep_assert_none_held_once();
966 
967 	points = kmalloc_array(count, sizeof(*points), GFP_KERNEL);
968 	if (points == NULL)
969 		return -ENOMEM;
970 
971 	if (!user_points) {
972 		memset(points, 0, count * sizeof(uint64_t));
973 
974 	} else if (copy_from_user(points, user_points,
975 				  sizeof(uint64_t) * count)) {
976 		timeout = -EFAULT;
977 		goto err_free_points;
978 	}
979 
980 	entries = kcalloc(count, sizeof(*entries), GFP_KERNEL);
981 	if (!entries) {
982 		timeout = -ENOMEM;
983 		goto err_free_points;
984 	}
985 	/* Walk the list of sync objects and initialize entries.  We do
986 	 * this up-front so that we can properly return -EINVAL if there is
987 	 * a syncobj with a missing fence and then never have the chance of
988 	 * returning -EINVAL again.
989 	 */
990 	signaled_count = 0;
991 	for (i = 0; i < count; ++i) {
992 		struct dma_fence *fence;
993 
994 		entries[i].task = current;
995 		entries[i].point = points[i];
996 		fence = drm_syncobj_fence_get(syncobjs[i]);
997 		if (!fence || dma_fence_chain_find_seqno(&fence, points[i])) {
998 			dma_fence_put(fence);
999 			if (flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT) {
1000 				continue;
1001 			} else {
1002 				timeout = -EINVAL;
1003 				goto cleanup_entries;
1004 			}
1005 		}
1006 
1007 		if (fence)
1008 			entries[i].fence = fence;
1009 		else
1010 			entries[i].fence = dma_fence_get_stub();
1011 
1012 		if ((flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_AVAILABLE) ||
1013 		    dma_fence_is_signaled(entries[i].fence)) {
1014 			if (signaled_count == 0 && idx)
1015 				*idx = i;
1016 			signaled_count++;
1017 		}
1018 	}
1019 
1020 	if (signaled_count == count ||
1021 	    (signaled_count > 0 &&
1022 	     !(flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL)))
1023 		goto cleanup_entries;
1024 
1025 	/* There's a very annoying laxness in the dma_fence API here, in
1026 	 * that backends are not required to automatically report when a
1027 	 * fence is signaled prior to fence->ops->enable_signaling() being
1028 	 * called.  So here if we fail to match signaled_count, we need to
1029 	 * fallthough and try a 0 timeout wait!
1030 	 */
1031 
1032 	if (flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT) {
1033 		for (i = 0; i < count; ++i)
1034 			drm_syncobj_fence_add_wait(syncobjs[i], &entries[i]);
1035 	}
1036 
1037 	do {
1038 		set_current_state(TASK_INTERRUPTIBLE);
1039 
1040 		signaled_count = 0;
1041 		for (i = 0; i < count; ++i) {
1042 			fence = entries[i].fence;
1043 			if (!fence)
1044 				continue;
1045 
1046 			if ((flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_AVAILABLE) ||
1047 			    dma_fence_is_signaled(fence) ||
1048 			    (!entries[i].fence_cb.func &&
1049 			     dma_fence_add_callback(fence,
1050 						    &entries[i].fence_cb,
1051 						    syncobj_wait_fence_func))) {
1052 				/* The fence has been signaled */
1053 				if (flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL) {
1054 					signaled_count++;
1055 				} else {
1056 					if (idx)
1057 						*idx = i;
1058 					goto done_waiting;
1059 				}
1060 			}
1061 		}
1062 
1063 		if (signaled_count == count)
1064 			goto done_waiting;
1065 
1066 		if (timeout == 0) {
1067 			timeout = -ETIME;
1068 			goto done_waiting;
1069 		}
1070 
1071 		if (signal_pending(current)) {
1072 			timeout = -ERESTARTSYS;
1073 			goto done_waiting;
1074 		}
1075 
1076 		timeout = schedule_timeout(timeout);
1077 	} while (1);
1078 
1079 done_waiting:
1080 	__set_current_state(TASK_RUNNING);
1081 
1082 cleanup_entries:
1083 	for (i = 0; i < count; ++i) {
1084 		drm_syncobj_remove_wait(syncobjs[i], &entries[i]);
1085 		if (entries[i].fence_cb.func)
1086 			dma_fence_remove_callback(entries[i].fence,
1087 						  &entries[i].fence_cb);
1088 		dma_fence_put(entries[i].fence);
1089 	}
1090 	kfree(entries);
1091 
1092 err_free_points:
1093 	kfree(points);
1094 
1095 	return timeout;
1096 }
1097 
1098 /**
1099  * drm_timeout_abs_to_jiffies - calculate jiffies timeout from absolute value
1100  *
1101  * @timeout_nsec: timeout nsec component in ns, 0 for poll
1102  *
1103  * Calculate the timeout in jiffies from an absolute time in sec/nsec.
1104  */
1105 signed long drm_timeout_abs_to_jiffies(int64_t timeout_nsec)
1106 {
1107 	ktime_t abs_timeout, now;
1108 	u64 timeout_ns, timeout_jiffies64;
1109 
1110 	/* make 0 timeout means poll - absolute 0 doesn't seem valid */
1111 	if (timeout_nsec == 0)
1112 		return 0;
1113 
1114 	abs_timeout = ns_to_ktime(timeout_nsec);
1115 	now = ktime_get();
1116 
1117 	if (!ktime_after(abs_timeout, now))
1118 		return 0;
1119 
1120 	timeout_ns = ktime_to_ns(ktime_sub(abs_timeout, now));
1121 
1122 	timeout_jiffies64 = nsecs_to_jiffies64(timeout_ns);
1123 	/*  clamp timeout to avoid infinite timeout */
1124 	if (timeout_jiffies64 >= MAX_SCHEDULE_TIMEOUT - 1)
1125 		return MAX_SCHEDULE_TIMEOUT - 1;
1126 
1127 	return timeout_jiffies64 + 1;
1128 }
1129 EXPORT_SYMBOL(drm_timeout_abs_to_jiffies);
1130 
1131 static int drm_syncobj_array_wait(struct drm_device *dev,
1132 				  struct drm_file *file_private,
1133 				  struct drm_syncobj_wait *wait,
1134 				  struct drm_syncobj_timeline_wait *timeline_wait,
1135 				  struct drm_syncobj **syncobjs, bool timeline)
1136 {
1137 	signed long timeout = 0;
1138 	uint32_t first = ~0;
1139 
1140 	if (!timeline) {
1141 		timeout = drm_timeout_abs_to_jiffies(wait->timeout_nsec);
1142 		timeout = drm_syncobj_array_wait_timeout(syncobjs,
1143 							 NULL,
1144 							 wait->count_handles,
1145 							 wait->flags,
1146 							 timeout, &first);
1147 		if (timeout < 0)
1148 			return timeout;
1149 		wait->first_signaled = first;
1150 	} else {
1151 		timeout = drm_timeout_abs_to_jiffies(timeline_wait->timeout_nsec);
1152 		timeout = drm_syncobj_array_wait_timeout(syncobjs,
1153 							 u64_to_user_ptr(timeline_wait->points),
1154 							 timeline_wait->count_handles,
1155 							 timeline_wait->flags,
1156 							 timeout, &first);
1157 		if (timeout < 0)
1158 			return timeout;
1159 		timeline_wait->first_signaled = first;
1160 	}
1161 	return 0;
1162 }
1163 
1164 static int drm_syncobj_array_find(struct drm_file *file_private,
1165 				  void __user *user_handles,
1166 				  uint32_t count_handles,
1167 				  struct drm_syncobj ***syncobjs_out)
1168 {
1169 	uint32_t i, *handles;
1170 	struct drm_syncobj **syncobjs;
1171 	int ret;
1172 
1173 	handles = kmalloc_array(count_handles, sizeof(*handles), GFP_KERNEL);
1174 	if (handles == NULL)
1175 		return -ENOMEM;
1176 
1177 	if (copy_from_user(handles, user_handles,
1178 			   sizeof(uint32_t) * count_handles)) {
1179 		ret = -EFAULT;
1180 		goto err_free_handles;
1181 	}
1182 
1183 	syncobjs = kmalloc_array(count_handles, sizeof(*syncobjs), GFP_KERNEL);
1184 	if (syncobjs == NULL) {
1185 		ret = -ENOMEM;
1186 		goto err_free_handles;
1187 	}
1188 
1189 	for (i = 0; i < count_handles; i++) {
1190 		syncobjs[i] = drm_syncobj_find(file_private, handles[i]);
1191 		if (!syncobjs[i]) {
1192 			ret = -ENOENT;
1193 			goto err_put_syncobjs;
1194 		}
1195 	}
1196 
1197 	kfree(handles);
1198 	*syncobjs_out = syncobjs;
1199 	return 0;
1200 
1201 err_put_syncobjs:
1202 	while (i-- > 0)
1203 		drm_syncobj_put(syncobjs[i]);
1204 	kfree(syncobjs);
1205 err_free_handles:
1206 	kfree(handles);
1207 
1208 	return ret;
1209 }
1210 
1211 static void drm_syncobj_array_free(struct drm_syncobj **syncobjs,
1212 				   uint32_t count)
1213 {
1214 	uint32_t i;
1215 
1216 	for (i = 0; i < count; i++)
1217 		drm_syncobj_put(syncobjs[i]);
1218 	kfree(syncobjs);
1219 }
1220 
1221 int
1222 drm_syncobj_wait_ioctl(struct drm_device *dev, void *data,
1223 		       struct drm_file *file_private)
1224 {
1225 	struct drm_syncobj_wait *args = data;
1226 	struct drm_syncobj **syncobjs;
1227 	int ret = 0;
1228 
1229 	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
1230 		return -EOPNOTSUPP;
1231 
1232 	if (args->flags & ~(DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL |
1233 			    DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT))
1234 		return -EINVAL;
1235 
1236 	if (args->count_handles == 0)
1237 		return -EINVAL;
1238 
1239 	ret = drm_syncobj_array_find(file_private,
1240 				     u64_to_user_ptr(args->handles),
1241 				     args->count_handles,
1242 				     &syncobjs);
1243 	if (ret < 0)
1244 		return ret;
1245 
1246 	ret = drm_syncobj_array_wait(dev, file_private,
1247 				     args, NULL, syncobjs, false);
1248 
1249 	drm_syncobj_array_free(syncobjs, args->count_handles);
1250 
1251 	return ret;
1252 }
1253 
1254 int
1255 drm_syncobj_timeline_wait_ioctl(struct drm_device *dev, void *data,
1256 				struct drm_file *file_private)
1257 {
1258 	struct drm_syncobj_timeline_wait *args = data;
1259 	struct drm_syncobj **syncobjs;
1260 	int ret = 0;
1261 
1262 	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE))
1263 		return -EOPNOTSUPP;
1264 
1265 	if (args->flags & ~(DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL |
1266 			    DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT |
1267 			    DRM_SYNCOBJ_WAIT_FLAGS_WAIT_AVAILABLE))
1268 		return -EINVAL;
1269 
1270 	if (args->count_handles == 0)
1271 		return -EINVAL;
1272 
1273 	ret = drm_syncobj_array_find(file_private,
1274 				     u64_to_user_ptr(args->handles),
1275 				     args->count_handles,
1276 				     &syncobjs);
1277 	if (ret < 0)
1278 		return ret;
1279 
1280 	ret = drm_syncobj_array_wait(dev, file_private,
1281 				     NULL, args, syncobjs, true);
1282 
1283 	drm_syncobj_array_free(syncobjs, args->count_handles);
1284 
1285 	return ret;
1286 }
1287 
1288 
1289 int
1290 drm_syncobj_reset_ioctl(struct drm_device *dev, void *data,
1291 			struct drm_file *file_private)
1292 {
1293 	struct drm_syncobj_array *args = data;
1294 	struct drm_syncobj **syncobjs;
1295 	uint32_t i;
1296 	int ret;
1297 
1298 	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
1299 		return -EOPNOTSUPP;
1300 
1301 	if (args->pad != 0)
1302 		return -EINVAL;
1303 
1304 	if (args->count_handles == 0)
1305 		return -EINVAL;
1306 
1307 	ret = drm_syncobj_array_find(file_private,
1308 				     u64_to_user_ptr(args->handles),
1309 				     args->count_handles,
1310 				     &syncobjs);
1311 	if (ret < 0)
1312 		return ret;
1313 
1314 	for (i = 0; i < args->count_handles; i++)
1315 		drm_syncobj_replace_fence(syncobjs[i], NULL);
1316 
1317 	drm_syncobj_array_free(syncobjs, args->count_handles);
1318 
1319 	return 0;
1320 }
1321 
1322 int
1323 drm_syncobj_signal_ioctl(struct drm_device *dev, void *data,
1324 			 struct drm_file *file_private)
1325 {
1326 	struct drm_syncobj_array *args = data;
1327 	struct drm_syncobj **syncobjs;
1328 	uint32_t i;
1329 	int ret;
1330 
1331 	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
1332 		return -EOPNOTSUPP;
1333 
1334 	if (args->pad != 0)
1335 		return -EINVAL;
1336 
1337 	if (args->count_handles == 0)
1338 		return -EINVAL;
1339 
1340 	ret = drm_syncobj_array_find(file_private,
1341 				     u64_to_user_ptr(args->handles),
1342 				     args->count_handles,
1343 				     &syncobjs);
1344 	if (ret < 0)
1345 		return ret;
1346 
1347 	for (i = 0; i < args->count_handles; i++) {
1348 		ret = drm_syncobj_assign_null_handle(syncobjs[i]);
1349 		if (ret < 0)
1350 			break;
1351 	}
1352 
1353 	drm_syncobj_array_free(syncobjs, args->count_handles);
1354 
1355 	return ret;
1356 }
1357 
1358 int
1359 drm_syncobj_timeline_signal_ioctl(struct drm_device *dev, void *data,
1360 				  struct drm_file *file_private)
1361 {
1362 	struct drm_syncobj_timeline_array *args = data;
1363 	struct drm_syncobj **syncobjs;
1364 	struct dma_fence_chain **chains;
1365 	uint64_t *points;
1366 	uint32_t i, j;
1367 	int ret;
1368 
1369 	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE))
1370 		return -EOPNOTSUPP;
1371 
1372 	if (args->flags != 0)
1373 		return -EINVAL;
1374 
1375 	if (args->count_handles == 0)
1376 		return -EINVAL;
1377 
1378 	ret = drm_syncobj_array_find(file_private,
1379 				     u64_to_user_ptr(args->handles),
1380 				     args->count_handles,
1381 				     &syncobjs);
1382 	if (ret < 0)
1383 		return ret;
1384 
1385 	points = kmalloc_array(args->count_handles, sizeof(*points),
1386 			       GFP_KERNEL);
1387 	if (!points) {
1388 		ret = -ENOMEM;
1389 		goto out;
1390 	}
1391 	if (!u64_to_user_ptr(args->points)) {
1392 		memset(points, 0, args->count_handles * sizeof(uint64_t));
1393 	} else if (copy_from_user(points, u64_to_user_ptr(args->points),
1394 				  sizeof(uint64_t) * args->count_handles)) {
1395 		ret = -EFAULT;
1396 		goto err_points;
1397 	}
1398 
1399 	chains = kmalloc_array(args->count_handles, sizeof(void *), GFP_KERNEL);
1400 	if (!chains) {
1401 		ret = -ENOMEM;
1402 		goto err_points;
1403 	}
1404 	for (i = 0; i < args->count_handles; i++) {
1405 		chains[i] = kzalloc(sizeof(struct dma_fence_chain), GFP_KERNEL);
1406 		if (!chains[i]) {
1407 			for (j = 0; j < i; j++)
1408 				kfree(chains[j]);
1409 			ret = -ENOMEM;
1410 			goto err_chains;
1411 		}
1412 	}
1413 
1414 	for (i = 0; i < args->count_handles; i++) {
1415 		struct dma_fence *fence = dma_fence_get_stub();
1416 
1417 		drm_syncobj_add_point(syncobjs[i], chains[i],
1418 				      fence, points[i]);
1419 		dma_fence_put(fence);
1420 	}
1421 err_chains:
1422 	kfree(chains);
1423 err_points:
1424 	kfree(points);
1425 out:
1426 	drm_syncobj_array_free(syncobjs, args->count_handles);
1427 
1428 	return ret;
1429 }
1430 
1431 int drm_syncobj_query_ioctl(struct drm_device *dev, void *data,
1432 			    struct drm_file *file_private)
1433 {
1434 	struct drm_syncobj_timeline_array *args = data;
1435 	struct drm_syncobj **syncobjs;
1436 	uint64_t __user *points = u64_to_user_ptr(args->points);
1437 	uint32_t i;
1438 	int ret;
1439 
1440 	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE))
1441 		return -EOPNOTSUPP;
1442 
1443 	if (args->flags & ~DRM_SYNCOBJ_QUERY_FLAGS_LAST_SUBMITTED)
1444 		return -EINVAL;
1445 
1446 	if (args->count_handles == 0)
1447 		return -EINVAL;
1448 
1449 	ret = drm_syncobj_array_find(file_private,
1450 				     u64_to_user_ptr(args->handles),
1451 				     args->count_handles,
1452 				     &syncobjs);
1453 	if (ret < 0)
1454 		return ret;
1455 
1456 	for (i = 0; i < args->count_handles; i++) {
1457 		struct dma_fence_chain *chain;
1458 		struct dma_fence *fence;
1459 		uint64_t point;
1460 
1461 		fence = drm_syncobj_fence_get(syncobjs[i]);
1462 		chain = to_dma_fence_chain(fence);
1463 		if (chain) {
1464 			struct dma_fence *iter, *last_signaled =
1465 				dma_fence_get(fence);
1466 
1467 			if (args->flags &
1468 			    DRM_SYNCOBJ_QUERY_FLAGS_LAST_SUBMITTED) {
1469 				point = fence->seqno;
1470 			} else {
1471 				dma_fence_chain_for_each(iter, fence) {
1472 					if (iter->context != fence->context) {
1473 						dma_fence_put(iter);
1474 						/* It is most likely that timeline has
1475 						* unorder points. */
1476 						break;
1477 					}
1478 					dma_fence_put(last_signaled);
1479 					last_signaled = dma_fence_get(iter);
1480 				}
1481 				point = dma_fence_is_signaled(last_signaled) ?
1482 					last_signaled->seqno :
1483 					to_dma_fence_chain(last_signaled)->prev_seqno;
1484 			}
1485 			dma_fence_put(last_signaled);
1486 		} else {
1487 			point = 0;
1488 		}
1489 		dma_fence_put(fence);
1490 		ret = copy_to_user(&points[i], &point, sizeof(uint64_t));
1491 		ret = ret ? -EFAULT : 0;
1492 		if (ret)
1493 			break;
1494 	}
1495 	drm_syncobj_array_free(syncobjs, args->count_handles);
1496 
1497 	return ret;
1498 }
1499