summaryrefslogtreecommitdiffstats
path: root/drivers/gpu/drm/drm_syncobj.c
blob: 42d46414f767964a0161fc66ad1ce5662279bcf1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
/*
 * Copyright 2017 Red Hat
 * Parts ported from amdgpu (fence wait code).
 * Copyright 2016 Advanced Micro Devices, Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 *
 * Authors:
 *
 */

/**
 * DOC: Overview
 *
 * DRM synchronisation objects (syncobj, see struct &drm_syncobj) provide a
 * container for a synchronization primitive which can be used by userspace
 * to explicitly synchronize GPU commands, can be shared between userspace
 * processes, and can be shared between different DRM drivers.
 * Their primary use-case is to implement Vulkan fences and semaphores.
 * The syncobj userspace API provides ioctls for several operations:
 *
 *  - Creation and destruction of syncobjs
 *  - Import and export of syncobjs to/from a syncobj file descriptor
 *  - Import and export a syncobj's underlying fence to/from a sync file
 *  - Reset a syncobj (set its fence to NULL)
 *  - Signal a syncobj (set a trivially signaled fence)
 *  - Wait for a syncobj's fence to appear and be signaled
 *
 * The syncobj userspace API also provides operations to manipulate a syncobj
 * in terms of a timeline of struct &dma_fence_chain rather than a single
 * struct &dma_fence, through the following operations:
 *
 *   - Signal a given point on the timeline
 *   - Wait for a given point to appear and/or be signaled
 *   - Import and export from/to a given point of a timeline
 *
 * At it's core, a syncobj is simply a wrapper around a pointer to a struct
 * &dma_fence which may be NULL.
 * When a syncobj is first created, its pointer is either NULL or a pointer
 * to an already signaled fence depending on whether the
 * &DRM_SYNCOBJ_CREATE_SIGNALED flag is passed to
 * &DRM_IOCTL_SYNCOBJ_CREATE.
 *
 * If the syncobj is considered as a binary (its state is either signaled or
 * unsignaled) primitive, when GPU work is enqueued in a DRM driver to signal
 * the syncobj, the syncobj's fence is replaced with a fence which will be
 * signaled by the completion of that work.
 * If the syncobj is considered as a timeline primitive, when GPU work is
 * enqueued in a DRM driver to signal the a given point of the syncobj, a new
 * struct &dma_fence_chain pointing to the DRM driver's fence and also
 * pointing to the previous fence that was in the syncobj. The new struct
 * &dma_fence_chain fence replace the syncobj's fence and will be signaled by
 * completion of the DRM driver's work and also any work associated with the
 * fence previously in the syncobj.
 *
 * When GPU work which waits on a syncobj is enqueued in a DRM driver, at the
 * time the work is enqueued, it waits on the syncobj's fence before
 * submitting the work to hardware. That fence is either :
 *
 *    - The syncobj's current fence if the syncobj is considered as a binary
 *      primitive.
 *    - The struct &dma_fence associated with a given point if the syncobj is
 *      considered as a timeline primitive.
 *
 * If the syncobj's fence is NULL or not present in the syncobj's timeline,
 * the enqueue operation is expected to fail.
 *
 * With binary syncobj, all manipulation of the syncobjs's fence happens in
 * terms of the current fence at the time the ioctl is called by userspace
 * regardless of whether that operation is an immediate host-side operation
 * (signal or reset) or or an operation which is enqueued in some driver
 * queue. &DRM_IOCTL_SYNCOBJ_RESET and &DRM_IOCTL_SYNCOBJ_SIGNAL can be used
 * to manipulate a syncobj from the host by resetting its pointer to NULL or
 * setting its pointer to a fence which is already signaled.
 *
 * With a timeline syncobj, all manipulation of the synobj's fence happens in
 * terms of a u64 value referring to point in the timeline. See
 * dma_fence_chain_find_seqno() to see how a given point is found in the
 * timeline.
 *
 * Note that applications should be careful to always use timeline set of
 * ioctl() when dealing with syncobj considered as timeline. Using a binary
 * set of ioctl() with a syncobj considered as timeline could result incorrect
 * synchronization. The use of binary syncobj is supported through the
 * timeline set of ioctl() by using a point value of 0, this will reproduce
 * the behavior of the binary set of ioctl() (for example replace the
 * syncobj's fence when signaling).
 *
 *
 * Host-side wait on syncobjs
 * --------------------------
 *
 * &DRM_IOCTL_SYNCOBJ_WAIT takes an array of syncobj handles and does a
 * host-side wait on all of the syncobj fences simultaneously.
 * If &DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL is set, the wait ioctl will wait on
 * all of the syncobj fences to be signaled before it returns.
 * Otherwise, it returns once at least one syncobj fence has been signaled
 * and the index of a signaled fence is written back to the client.
 *
 * Unlike the enqueued GPU work dependencies which fail if they see a NULL
 * fence in a syncobj, if &DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT is set,
 * the host-side wait will first wait for the syncobj to receive a non-NULL
 * fence and then wait on that fence.
 * If &DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT is not set and any one of the
 * syncobjs in the array has a NULL fence, -EINVAL will be returned.
 * Assuming the syncobj starts off with a NULL fence, this allows a client
 * to do a host wait in one thread (or process) which waits on GPU work
 * submitted in another thread (or process) without having to manually
 * synchronize between the two.
 * This requirement is inherited from the Vulkan fence API.
 *
 * Similarly, &DRM_IOCTL_SYNCOBJ_TIMELINE_WAIT takes an array of syncobj
 * handles as well as an array of u64 points and does a host-side wait on all
 * of syncobj fences at the given points simultaneously.
 *
 * &DRM_IOCTL_SYNCOBJ_TIMELINE_WAIT also adds the ability to wait for a given
 * fence to materialize on the timeline without waiting for the fence to be
 * signaled by using the &DRM_SYNCOBJ_WAIT_FLAGS_WAIT_AVAILABLE flag. This
 * requirement is inherited from the wait-before-signal behavior required by
 * the Vulkan timeline semaphore API.
 *
 *
 * Import/export of syncobjs
 * -------------------------
 *
 * &DRM_IOCTL_SYNCOBJ_FD_TO_HANDLE and &DRM_IOCTL_SYNCOBJ_HANDLE_TO_FD
 * provide two mechanisms for import/export of syncobjs.
 *
 * The first lets the client import or export an entire syncobj to a file
 * descriptor.
 * These fd's are opaque and have no other use case, except passing the
 * syncobj between processes.
 * All exported file descriptors and any syncobj handles created as a
 * result of importing those file descriptors own a reference to the
 * same underlying struct &drm_syncobj and the syncobj can be used
 * persistently across all the processes with which it is shared.
 * The syncobj is freed only once the last reference is dropped.
 * Unlike dma-buf, importing a syncobj creates a new handle (with its own
 * reference) for every import instead of de-duplicating.
 * The primary use-case of this persistent import/export is for shared
 * Vulkan fences and semaphores.
 *
 * The second import/export mechanism, which is indicated by
 * &DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE or
 * &DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE lets the client
 * import/export the syncobj's current fence from/to a &sync_file.
 * When a syncobj is exported to a sync file, that sync file wraps the
 * sycnobj's fence at the time of export and any later signal or reset
 * operations on the syncobj will not affect the exported sync file.
 * When a sync file is imported into a syncobj, the syncobj's fence is set
 * to the fence wrapped by that sync file.
 * Because sync files are immutable, resetting or signaling the syncobj
 * will not affect any sync files whose fences have been imported into the
 * syncobj.
 *
 *
 * Import/export of timeline points in timeline syncobjs
 * -----------------------------------------------------
 *
 * &DRM_IOCTL_SYNCOBJ_TRANSFER provides a mechanism to transfer a struct
 * &dma_fence_chain of a syncobj at a given u64 point to another u64 point
 * into another syncobj.
 *
 * Note that if you want to transfer a struct &dma_fence_chain from a given
 * point on a timeline syncobj from/into a binary syncobj, you can use the
 * point 0 to mean take/replace the fence in the syncobj.
 */

#include <linux/anon_inodes.h>
#include <linux/file.h>
#include <linux/fs.h>
#include <linux/sched/signal.h>
#include <linux/sync_file.h>
#include <linux/uaccess.h>

#include <drm/drm.h>
#include <drm/drm_drv.h>
#include <drm/drm_file.h>
#include <drm/drm_gem.h>
#include <drm/drm_print.h>
#include <drm/drm_syncobj.h>
#include <drm/drm_utils.h>

#include "drm_internal.h"

struct syncobj_wait_entry {
	struct list_head node;
	struct task_struct *task;
	struct dma_fence *fence;
	struct dma_fence_cb fence_cb;
	u64    point;
};

static void syncobj_wait_syncobj_func(struct drm_syncobj *syncobj,
				      struct syncobj_wait_entry *wait);

/**
 * drm_syncobj_find - lookup and reference a sync object.
 * @file_private: drm file private pointer
 * @handle: sync object handle to lookup.
 *
 * Returns a reference to the syncobj pointed to by handle or NULL. The
 * reference must be released by calling drm_syncobj_put().
 */
struct drm_syncobj *drm_syncobj_find(struct drm_file *file_private,
				     u32 handle)
{
	struct drm_syncobj *syncobj;

	spin_lock(&file_private->syncobj_table_lock);

	/* Check if we currently have a reference on the object */
	syncobj = idr_find(&file_private->syncobj_idr, handle);
	if (syncobj)
		drm_syncobj_get(syncobj);

	spin_unlock(&file_private->syncobj_table_lock);

	return syncobj;
}
EXPORT_SYMBOL(drm_syncobj_find);

static void drm_syncobj_fence_add_wait(struct drm_syncobj *syncobj,
				       struct syncobj_wait_entry *wait)
{
	struct dma_fence *fence;

	if (wait->fence)
		return;

	spin_lock(&syncobj->lock);
	/* We've already tried once to get a fence and failed.  Now that we
	 * have the lock, try one more time just to be sure we don't add a
	 * callback when a fence has already been set.
	 */
	fence = dma_fence_get(rcu_dereference_protected(syncobj->fence, 1));
	if (!fence || dma_fence_chain_find_seqno(&fence, wait->point)) {
		dma_fence_put(fence);
		list_add_tail(&wait->node, &syncobj->cb_list);
	} else if (!fence) {
		wait->fence = dma_fence_get_stub();
	} else {
		wait->fence = fence;
	}
	spin_unlock(&syncobj->lock);
}

static void drm_syncobj_remove_wait(struct drm_syncobj *syncobj,
				    struct syncobj_wait_entry *wait)
{
	if (!wait->node.next)
		return;

	spin_lock(&syncobj->lock);
	list_del_init(&wait->node);
	spin_unlock(&syncobj->lock);
}

/**
 * drm_syncobj_add_point - add new timeline point to the syncobj
 * @syncobj: sync object to add timeline point do
 * @chain: chain node to use to add the point
 * @fence: fence to encapsulate in the chain node
 * @point: sequence number to use for the point
 *
 * Add the chain node as new timeline point to the syncobj.
 */
void drm_syncobj_add_point(struct drm_syncobj *syncobj,
			   struct dma_fence_chain *chain,
			   struct dma_fence *fence,
			   uint64_t point)
{
	struct syncobj_wait_entry *cur, *tmp;
	struct dma_fence *prev;

	dma_fence_get(fence);

	spin_lock(&syncobj->lock);

	prev = drm_syncobj_fence_get(syncobj);
	/* You are adding an unorder point to timeline, which could cause payload returned from query_ioctl is 0! */
	if (prev && prev->seqno >= point)
		DRM_ERROR("You are adding an unorder point to timeline!\n");
	dma_fence_chain_init(chain, prev, fence, point);
	rcu_assign_pointer(syncobj->fence, &chain->base);

	list_for_each_entry_safe(cur, tmp, &syncobj->cb_list, node)
		syncobj_wait_syncobj_func(syncobj, cur);
	spin_unlock(&syncobj->lock);

	/* Walk the chain once to trigger garbage collection */
	dma_fence_chain_for_each(fence, prev);
	dma_fence_put(prev);
}
EXPORT_SYMBOL(drm_syncobj_add_point);

/**
 * drm_syncobj_replace_fence - replace fence in a sync object.
 * @syncobj: Sync object to replace fence in
 * @fence: fence to install in sync file.
 *
 * This replaces the fence on a sync object.
 */
void drm_syncobj_replace_fence(struct drm_syncobj *syncobj,
			       struct dma_fence *fence)
{
	struct dma_fence *old_fence;
	struct syncobj_wait_entry *cur, *tmp;

	if (fence)
		dma_fence_get(fence);

	spin_lock(&syncobj->lock);

	old_fence = rcu_dereference_protected(syncobj->fence,
					      lockdep_is_held(&syncobj->lock));
	rcu_assign_pointer(syncobj->fence, fence);

	if (fence != old_fence) {
		list_for_each_entry_safe(cur, tmp, &syncobj->cb_list, node)
			syncobj_wait_syncobj_func(syncobj, cur);
	}

	spin_unlock(&syncobj->lock);

	dma_fence_put(old_fence);
}
EXPORT_SYMBOL(drm_syncobj_replace_fence);

/**
 * drm_syncobj_assign_null_handle - assign a stub fence to the sync object
 * @syncobj: sync object to assign the fence on
 *
 * Assign a already signaled stub fence to the sync object.
 */
static void drm_syncobj_assign_null_handle(struct drm_syncobj *syncobj)
{
	struct dma_fence *fence = dma_fence_get_stub();

	drm_syncobj_replace_fence(syncobj, fence);
	dma_fence_put(fence);
}

/* 5s default for wait submission */
#define DRM_SYNCOBJ_WAIT_FOR_SUBMIT_TIMEOUT 5000000000ULL
/**
 * drm_syncobj_find_fence - lookup and reference the fence in a sync object
 * @file_private: drm file private pointer
 * @handle: sync object handle to lookup.
 * @point: timeline point
 * @flags: DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT or not
 * @fence: out parameter for the fence
 *
 * This is just a convenience function that combines drm_syncobj_find() and
 * drm_syncobj_fence_get().
 *
 * Returns 0 on success or a negative error value on failure. On success @fence
 * contains a reference to the fence, which must be released by calling
 * dma_fence_put().
 */
int drm_syncobj_find_fence(struct drm_file *file_private,
			   u32 handle, u64 point, u64 flags,
			   struct dma_fence **fence)
{
	struct drm_syncobj *syncobj = drm_syncobj_find(file_private, handle);
	struct syncobj_wait_entry wait;
	u64 timeout = nsecs_to_jiffies64(DRM_SYNCOBJ_WAIT_FOR_SUBMIT_TIMEOUT);
	int ret;

	if (!syncobj)
		return -ENOENT;

	*fence = drm_syncobj_fence_get(syncobj);
	drm_syncobj_put(syncobj);

	if (*fence) {
		ret = dma_fence_chain_find_seqno(fence, point);
		if (!ret)
			return 0;
		dma_fence_put(*fence);
	} else {
		ret = -EINVAL;
	}

	if (!(flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT))
		return ret;

	memset(&wait, 0, sizeof(wait));
	wait.task = current;
	wait.point = point;
	drm_syncobj_fence_add_wait(syncobj, &wait);

	do {
		set_current_state(TASK_INTERRUPTIBLE);
		if (wait.fence) {
			ret = 0;
			break;
		}
                if (timeout == 0) {
                        ret = -ETIME;
                        break;
                }

		if (signal_pending(current)) {
			ret = -ERESTARTSYS;
			break;
		}

                timeout = schedule_timeout(timeout);
	} while (1);

	__set_current_state(TASK_RUNNING);
	*fence = wait.fence;

	if (wait.node.next)
		drm_syncobj_remove_wait(syncobj, &wait);

	return ret;
}
EXPORT_SYMBOL(drm_syncobj_find_fence);

/**
 * drm_syncobj_free - free a sync object.
 * @kref: kref to free.
 *
 * Only to be called from kref_put in drm_syncobj_put.
 */
void drm_syncobj_free(struct kref *kref)
{
	struct drm_syncobj *syncobj = container_of(kref,
						   struct drm_syncobj,
						   refcount);
	drm_syncobj_replace_fence(syncobj, NULL);
	kfree(syncobj);
}
EXPORT_SYMBOL(drm_syncobj_free);

/**
 * drm_syncobj_create - create a new syncobj
 * @out_syncobj: returned syncobj
 * @flags: DRM_SYNCOBJ_* flags
 * @fence: if non-NULL, the syncobj will represent this fence
 *
 * This is the first function to create a sync object. After creating, drivers
 * probably want to make it available to userspace, either through
 * drm_syncobj_get_handle() or drm_syncobj_get_fd().
 *
 * Returns 0 on success or a negative error value on failure.
 */
int drm_syncobj_create(struct drm_syncobj **out_syncobj, uint32_t flags,
		       struct dma_fence *fence)
{
	struct drm_syncobj *syncobj;

	syncobj = kzalloc(sizeof(struct drm_syncobj), GFP_KERNEL);
	if (!syncobj)
		return -ENOMEM;

	kref_init(&syncobj->refcount);
	INIT_LIST_HEAD(&syncobj->cb_list);
	spin_lock_init(&syncobj->lock);

	if (flags & DRM_SYNCOBJ_CREATE_SIGNALED)
		drm_syncobj_assign_null_handle(syncobj);

	if (fence)
		drm_syncobj_replace_fence(syncobj, fence);

	*out_syncobj = syncobj;
	return 0;
}
EXPORT_SYMBOL(drm_syncobj_create);

/**
 * drm_syncobj_get_handle - get a handle from a syncobj
 * @file_private: drm file private pointer
 * @syncobj: Sync object to export
 * @handle: out parameter with the new handle
 *
 * Exports a sync object created with drm_syncobj_create() as a handle on
 * @file_private to userspace.
 *
 * Returns 0 on success or a negative error value on failure.
 */
int drm_syncobj_get_handle(struct drm_file *file_private,
			   struct drm_syncobj *syncobj, u32 *handle)
{
	int ret;

	/* take a reference to put in the idr */
	drm_syncobj_get(syncobj);

	idr_preload(GFP_KERNEL);
	spin_lock(&file_private->syncobj_table_lock);
	ret = idr_alloc(&file_private->syncobj_idr, syncobj, 1, 0, GFP_NOWAIT);
	spin_unlock(&file_private->syncobj_table_lock);

	idr_preload_end();

	if (ret < 0) {
		drm_syncobj_put(syncobj);
		return ret;
	}

	*handle = ret;
	return 0;
}
EXPORT_SYMBOL(drm_syncobj_get_handle);

static int drm_syncobj_create_as_handle(struct drm_file *file_private,
					u32 *handle, uint32_t flags)
{
	int ret;
	struct drm_syncobj *syncobj;

	ret = drm_syncobj_create(&syncobj, flags, NULL);
	if (ret)
		return ret;

	ret = drm_syncobj_get_handle(file_private, syncobj, handle);
	drm_syncobj_put(syncobj);
	return ret;
}

static int drm_syncobj_destroy(struct drm_file *file_private,
			       u32 handle)
{
	struct drm_syncobj *syncobj;

	spin_lock(&file_private->syncobj_table_lock);
	syncobj = idr_remove(&file_private->syncobj_idr, handle);
	spin_unlock(&file_private->syncobj_table_lock);

	if (!syncobj)
		return -EINVAL;

	drm_syncobj_put(syncobj);
	return 0;
}

static int drm_syncobj_file_release(struct inode *inode, struct file *file)
{
	struct drm_syncobj *syncobj = file->private_data;

	drm_syncobj_put(syncobj);
	return 0;
}

static const struct file_operations drm_syncobj_file_fops = {
	.release = drm_syncobj_file_release,
};

/**
 * drm_syncobj_get_fd - get a file descriptor from a syncobj
 * @syncobj: Sync object to export
 * @p_fd: out parameter with the new file descriptor
 *
 * Exports a sync object created with drm_syncobj_create() as a file descriptor.
 *
 * Returns 0 on success or a negative error value on failure.
 */
int drm_syncobj_get_fd(struct drm_syncobj *syncobj, int *p_fd)
{
	struct file *file;
	int fd;

	fd = get_unused_fd_flags(O_CLOEXEC);
	if (fd < 0)
		return fd;

	file = anon_inode_getfile("syncobj_file",
				  &drm_syncobj_file_fops,
				  syncobj, 0);
	if (IS_ERR(file)) {
		put_unused_fd(fd);
		return PTR_ERR(file);
	}

	drm_syncobj_get(syncobj);
	fd_install(fd, file);

	*p_fd = fd;
	return 0;
}
EXPORT_SYMBOL(drm_syncobj_get_fd);

static int drm_syncobj_handle_to_fd(struct drm_file *file_private,
				    u32 handle, int *p_fd)
{
	struct drm_syncobj *syncobj = drm_syncobj_find(file_private, handle);
	int ret;

	if (!syncobj)
		return -EINVAL;

	ret = drm_syncobj_get_fd(syncobj, p_fd);
	drm_syncobj_put(syncobj);
	return ret;
}

static int drm_syncobj_fd_to_handle(struct drm_file *file_private,
				    int fd, u32 *handle)
{
	struct drm_syncobj *syncobj;
	struct fd f = fdget(fd);
	int ret;

	if (!f.file)
		return -EINVAL;

	if (f.file->f_op != &drm_syncobj_file_fops) {
		fdput(f);
		return -EINVAL;
	}

	/* take a reference to put in the idr */
	syncobj = f.file->private_data;
	drm_syncobj_get(syncobj);

	idr_preload(GFP_KERNEL);
	spin_lock(&file_private->syncobj_table_lock);
	ret = idr_alloc(&file_private->syncobj_idr, syncobj, 1, 0, GFP_NOWAIT);
	spin_unlock(&file_private->syncobj_table_lock);
	idr_preload_end();

	if (ret > 0) {
		*handle = ret;
		ret = 0;
	} else
		drm_syncobj_put(syncobj);

	fdput(f);
	return ret;
}

static int drm_syncobj_import_sync_file_fence(struct drm_file *file_private,
					      int fd, int handle)
{
	struct dma_fence *fence = sync_file_get_fence(fd);
	struct drm_syncobj *syncobj;

	if (!fence)
		return -EINVAL;

	syncobj = drm_syncobj_find(file_private, handle);
	if (!syncobj) {
		dma_fence_put(fence);
		return -ENOENT;
	}

	drm_syncobj_replace_fence(syncobj, fence);
	dma_fence_put(fence);
	drm_syncobj_put(syncobj);
	return 0;
}

static int drm_syncobj_export_sync_file(struct drm_file *file_private,
					int handle, int *p_fd)
{
	int ret;
	struct dma_fence *fence;
	struct sync_file *sync_file;
	int fd = get_unused_fd_flags(O_CLOEXEC);

	if (fd < 0)
		return fd;

	ret = drm_syncobj_find_fence(file_private, handle, 0, 0, &fence);
	if (ret)
		goto err_put_fd;

	sync_file = sync_file_create(fence);

	dma_fence_put(fence);

	if (!sync_file) {
		ret = -EINVAL;
		goto err_put_fd;
	}

	fd_install(fd, sync_file->file);

	*p_fd = fd;
	return 0;
err_put_fd:
	put_unused_fd(fd);
	return ret;
}
/**
 * drm_syncobj_open - initalizes syncobj file-private structures at devnode open time
 * @file_private: drm file-private structure to set up
 *
 * Called at device open time, sets up the structure for handling refcounting
 * of sync objects.
 */
void
drm_syncobj_open(struct drm_file *file_private)
{
	idr_init_base(&file_private->syncobj_idr, 1);
	spin_lock_init(&file_private->syncobj_table_lock);
}

static int
drm_syncobj_release_handle(int id, void *ptr, void *data)
{
	struct drm_syncobj *syncobj = ptr;

	drm_syncobj_put(syncobj);
	return 0;
}

/**
 * drm_syncobj_release - release file-private sync object resources
 * @file_private: drm file-private structure to clean up
 *
 * Called at close time when the filp is going away.
 *
 * Releases any remaining references on objects by this filp.
 */
void
drm_syncobj_release(struct drm_file *file_private)
{
	idr_for_each(&file_private->syncobj_idr,
		     &drm_syncobj_release_handle, file_private);
	idr_destroy(&file_private->syncobj_idr);
}

int
drm_syncobj_create_ioctl(struct drm_device *dev, void *data,
			 struct drm_file *file_private)
{
	struct drm_syncobj_create *args = data;

	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
		return -EOPNOTSUPP;

	/* no valid flags yet */
	if (args->flags & ~DRM_SYNCOBJ_CREATE_SIGNALED)
		return -EINVAL;

	return drm_syncobj_create_as_handle(file_private,
					    &args->handle, args->flags);
}

int
drm_syncobj_destroy_ioctl(struct drm_device *dev, void *data,
			  struct drm_file *file_private)
{
	struct drm_syncobj_destroy *args = data;

	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
		return -EOPNOTSUPP;

	/* make sure padding is empty */
	if (args->pad)
		return -EINVAL;
	return drm_syncobj_destroy(file_private, args->handle);
}

int
drm_syncobj_handle_to_fd_ioctl(struct drm_device *dev, void *data,
				   struct drm_file *file_private)
{
	struct drm_syncobj_handle *args = data;

	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
		return -EOPNOTSUPP;

	if (args->pad)
		return -EINVAL;

	if (args->flags != 0 &&
	    args->flags != DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE)
		return -EINVAL;

	if (args->flags & DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE)
		return drm_syncobj_export_sync_file(file_private, args->handle,
						    &args->fd);

	return drm_syncobj_handle_to_fd(file_private, args->handle,
					&args->fd);
}

int
drm_syncobj_fd_to_handle_ioctl(struct drm_device *dev, void *data,
				   struct drm_file *file_private)
{
	struct drm_syncobj_handle *args = data;

	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
		return -EOPNOTSUPP;

	if (args->pad)
		return -EINVAL;

	if (args->flags != 0 &&
	    args->flags != DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE)
		return -EINVAL;

	if (args->flags & DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE)
		return drm_syncobj_import_sync_file_fence(file_private,
							  args->fd,
							  args->handle);

	return drm_syncobj_fd_to_handle(file_private, args->fd,
					&args->handle);
}

static int drm_syncobj_transfer_to_timeline(struct drm_file *file_private,
					    struct drm_syncobj_transfer *args)
{
	struct drm_syncobj *timeline_syncobj = NULL;
	struct dma_fence *fence;
	struct dma_fence_chain *chain;
	int ret;

	timeline_syncobj = drm_syncobj_find(file_private, args->dst_handle);
	if (!timeline_syncobj) {
		return -ENOENT;
	}
	ret = drm_syncobj_find_fence(file_private, args->src_handle,
				     args->src_point, args->flags,
				     &fence);
	if (ret)
		goto err;
	chain = kzalloc(sizeof(struct dma_fence_chain), GFP_KERNEL);
	if (!chain) {
		ret = -ENOMEM;
		goto err1;
	}
	drm_syncobj_add_point(timeline_syncobj, chain, fence, args->dst_point);
err1:
	dma_fence_put(fence);
err:
	drm_syncobj_put(timeline_syncobj);

	return ret;
}

static int
drm_syncobj_transfer_to_binary(struct drm_file *file_private,
			       struct drm_syncobj_transfer *args)
{
	struct drm_syncobj *binary_syncobj = NULL;
	struct dma_fence *fence;
	int ret;

	binary_syncobj = drm_syncobj_find(file_private, args->dst_handle);
	if (!binary_syncobj)
		return -ENOENT;
	ret = drm_syncobj_find_fence(file_private, args->src_handle,
				     args->src_point, args->flags, &fence);
	if (ret)
		goto err;
	drm_syncobj_replace_fence(binary_syncobj, fence);
	dma_fence_put(fence);
err:
	drm_syncobj_put(binary_syncobj);

	return ret;
}
int
drm_syncobj_transfer_ioctl(struct drm_device *dev, void *data,
			   struct drm_file *file_private)
{
	struct drm_syncobj_transfer *args = data;
	int ret;

	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE))
		return -EOPNOTSUPP;

	if (args->pad)
		return -EINVAL;

	if (args->dst_point)
		ret = drm_syncobj_transfer_to_timeline(file_private, args);
	else
		ret = drm_syncobj_transfer_to_binary(file_private, args);

	return ret;
}

static void syncobj_wait_fence_func(struct dma_fence *fence,
				    struct dma_fence_cb *cb)
{
	struct syncobj_wait_entry *wait =
		container_of(cb, struct syncobj_wait_entry, fence_cb);

	wake_up_process(wait->task);
}

static void syncobj_wait_syncobj_func(struct drm_syncobj *syncobj,
				      struct syncobj_wait_entry *wait)
{
	struct dma_fence *fence;

	/* This happens inside the syncobj lock */
	fence = rcu_dereference_protected(syncobj->fence,
					  lockdep_is_held(&syncobj->lock));
	dma_fence_get(fence);
	if (!fence || dma_fence_chain_find_seqno(&fence, wait->point)) {
		dma_fence_put(fence);
		return;
	} else if (!fence) {
		wait->fence = dma_fence_get_stub();
	} else {
		wait->fence = fence;
	}

	wake_up_process(wait->task);
	list_del_init(&wait->node);
}

static signed long drm_syncobj_array_wait_timeout(struct drm_syncobj **syncobjs,
						  void __user *user_points,
						  uint32_t count,
						  uint32_t flags,
						  signed long timeout,
						  uint32_t *idx)
{
	struct syncobj_wait_entry *entries;
	struct dma_fence *fence;
	uint64_t *points;
	uint32_t signaled_count, i;

	points = kmalloc_array(count, sizeof(*points), GFP_KERNEL);
	if (points == NULL)
		return -ENOMEM;

	if (!user_points) {
		memset(points, 0, count * sizeof(uint64_t));

	} else if (copy_from_user(points, user_points,
				  sizeof(uint64_t) * count)) {
		timeout = -EFAULT;
		goto err_free_points;
	}

	entries = kcalloc(count, sizeof(*entries), GFP_KERNEL);
	if (!entries) {
		timeout = -ENOMEM;
		goto err_free_points;
	}
	/* Walk the list of sync objects and initialize entries.  We do
	 * this up-front so that we can properly return -EINVAL if there is
	 * a syncobj with a missing fence and then never have the chance of
	 * returning -EINVAL again.
	 */
	signaled_count = 0;
	for (i = 0; i < count; ++i) {
		struct dma_fence *fence;

		entries[i].task = current;
		entries[i].point = points[i];
		fence = drm_syncobj_fence_get(syncobjs[i]);
		if (!fence || dma_fence_chain_find_seqno(&fence, points[i])) {
			dma_fence_put(fence);
			if (flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT) {
				continue;
			} else {
				timeout = -EINVAL;
				goto cleanup_entries;
			}
		}

		if (fence)
			entries[i].fence = fence;
		else
			entries[i].fence = dma_fence_get_stub();

		if ((flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_AVAILABLE) ||
		    dma_fence_is_signaled(entries[i].fence)) {
			if (signaled_count == 0 && idx)
				*idx = i;
			signaled_count++;
		}
	}

	if (signaled_count == count ||
	    (signaled_count > 0 &&
	     !(flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL)))
		goto cleanup_entries;

	/* There's a very annoying laxness in the dma_fence API here, in
	 * that backends are not required to automatically report when a
	 * fence is signaled prior to fence->ops->enable_signaling() being
	 * called.  So here if we fail to match signaled_count, we need to
	 * fallthough and try a 0 timeout wait!
	 */

	if (flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT) {
		for (i = 0; i < count; ++i)
			drm_syncobj_fence_add_wait(syncobjs[i], &entries[i]);
	}

	do {
		set_current_state(TASK_INTERRUPTIBLE);

		signaled_count = 0;
		for (i = 0; i < count; ++i) {
			fence = entries[i].fence;
			if (!fence)
				continue;

			if ((flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_AVAILABLE) ||
			    dma_fence_is_signaled(fence) ||
			    (!entries[i].fence_cb.func &&
			     dma_fence_add_callback(fence,
						    &entries[i].fence_cb,
						    syncobj_wait_fence_func))) {
				/* The fence has been signaled */
				if (flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL) {
					signaled_count++;
				} else {
					if (idx)
						*idx = i;
					goto done_waiting;
				}
			}
		}

		if (signaled_count == count)
			goto done_waiting;

		if (timeout == 0) {
			timeout = -ETIME;
			goto done_waiting;
		}

		if (signal_pending(current)) {
			timeout = -ERESTARTSYS;
			goto done_waiting;
		}

		timeout = schedule_timeout(timeout);
	} while (1);

done_waiting:
	__set_current_state(TASK_RUNNING);

cleanup_entries:
	for (i = 0; i < count; ++i) {
		drm_syncobj_remove_wait(syncobjs[i], &entries[i]);
		if (entries[i].fence_cb.func)
			dma_fence_remove_callback(entries[i].fence,
						  &entries[i].fence_cb);
		dma_fence_put(entries[i].fence);
	}
	kfree(entries);

err_free_points:
	kfree(points);

	return timeout;
}

/**
 * drm_timeout_abs_to_jiffies - calculate jiffies timeout from absolute value
 *
 * @timeout_nsec: timeout nsec component in ns, 0 for poll
 *
 * Calculate the timeout in jiffies from an absolute time in sec/nsec.
 */
signed long drm_timeout_abs_to_jiffies(int64_t timeout_nsec)
{
	ktime_t abs_timeout, now;
	u64 timeout_ns, timeout_jiffies64;

	/* make 0 timeout means poll - absolute 0 doesn't seem valid */
	if (timeout_nsec == 0)
		return 0;

	abs_timeout = ns_to_ktime(timeout_nsec);
	now = ktime_get();

	if (!ktime_after(abs_timeout, now))
		return 0;

	timeout_ns = ktime_to_ns(ktime_sub(abs_timeout, now));

	timeout_jiffies64 = nsecs_to_jiffies64(timeout_ns);
	/*  clamp timeout to avoid infinite timeout */
	if (timeout_jiffies64 >= MAX_SCHEDULE_TIMEOUT - 1)
		return MAX_SCHEDULE_TIMEOUT - 1;

	return timeout_jiffies64 + 1;
}
EXPORT_SYMBOL(drm_timeout_abs_to_jiffies);

static int drm_syncobj_array_wait(struct drm_device *dev,
				  struct drm_file *file_private,
				  struct drm_syncobj_wait *wait,
				  struct drm_syncobj_timeline_wait *timeline_wait,
				  struct drm_syncobj **syncobjs, bool timeline)
{
	signed long timeout = 0;
	uint32_t first = ~0;

	if (!timeline) {
		timeout = drm_timeout_abs_to_jiffies(wait->timeout_nsec);
		timeout = drm_syncobj_array_wait_timeout(syncobjs,
							 NULL,
							 wait->count_handles,
							 wait->flags,
							 timeout, &first);
		if (timeout < 0)
			return timeout;
		wait->first_signaled = first;
	} else {
		timeout = drm_timeout_abs_to_jiffies(timeline_wait->timeout_nsec);
		timeout = drm_syncobj_array_wait_timeout(syncobjs,
							 u64_to_user_ptr(timeline_wait->points),
							 timeline_wait->count_handles,
							 timeline_wait->flags,
							 timeout, &first);
		if (timeout < 0)
			return timeout;
		timeline_wait->first_signaled = first;
	}
	return 0;
}

static int drm_syncobj_array_find(struct drm_file *file_private,
				  void __user *user_handles,
				  uint32_t count_handles,
				  struct drm_syncobj ***syncobjs_out)
{
	uint32_t i, *handles;
	struct drm_syncobj **syncobjs;
	int ret;

	handles = kmalloc_array(count_handles, sizeof(*handles), GFP_KERNEL);
	if (handles == NULL)
		return -ENOMEM;

	if (copy_from_user(handles, user_handles,
			   sizeof(uint32_t) * count_handles)) {
		ret = -EFAULT;
		goto err_free_handles;
	}

	syncobjs = kmalloc_array(count_handles, sizeof(*syncobjs), GFP_KERNEL);
	if (syncobjs == NULL) {
		ret = -ENOMEM;
		goto err_free_handles;
	}

	for (i = 0; i < count_handles; i++) {
		syncobjs[i] = drm_syncobj_find(file_private, handles[i]);
		if (!syncobjs[i]) {
			ret = -ENOENT;
			goto err_put_syncobjs;
		}
	}

	kfree(handles);
	*syncobjs_out = syncobjs;
	return 0;

err_put_syncobjs:
	while (i-- > 0)
		drm_syncobj_put(syncobjs[i]);
	kfree(syncobjs);
err_free_handles:
	kfree(handles);

	return ret;
}

static void drm_syncobj_array_free(struct drm_syncobj **syncobjs,
				   uint32_t count)
{
	uint32_t i;
	for (i = 0; i < count; i++)
		drm_syncobj_put(syncobjs[i]);
	kfree(syncobjs);
}

int
drm_syncobj_wait_ioctl(struct drm_device *dev, void *data,
		       struct drm_file *file_private)
{
	struct drm_syncobj_wait *args = data;
	struct drm_syncobj **syncobjs;
	int ret = 0;

	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
		return -EOPNOTSUPP;

	if (args->flags & ~(DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL |
			    DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT))
		return -EINVAL;

	if (args->count_handles == 0)
		return -EINVAL;

	ret = drm_syncobj_array_find(file_private,
				     u64_to_user_ptr(args->handles),
				     args->count_handles,
				     &syncobjs);
	if (ret < 0)
		return ret;

	ret = drm_syncobj_array_wait(dev, file_private,
				     args, NULL, syncobjs, false);

	drm_syncobj_array_free(syncobjs, args->count_handles);

	return ret;
}

int
drm_syncobj_timeline_wait_ioctl(struct drm_device *dev, void *data,
				struct drm_file *file_private)
{
	struct drm_syncobj_timeline_wait *args = data;
	struct drm_syncobj **syncobjs;
	int ret = 0;

	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE))
		return -EOPNOTSUPP;

	if (args->flags & ~(DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL |
			    DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT |
			    DRM_SYNCOBJ_WAIT_FLAGS_WAIT_AVAILABLE))
		return -EINVAL;

	if (args->count_handles == 0)
		return -EINVAL;

	ret = drm_syncobj_array_find(file_private,
				     u64_to_user_ptr(args->handles),
				     args->count_handles,
				     &syncobjs);
	if (ret < 0)
		return ret;

	ret = drm_syncobj_array_wait(dev, file_private,
				     NULL, args, syncobjs, true);

	drm_syncobj_array_free(syncobjs, args->count_handles);

	return ret;
}


int
drm_syncobj_reset_ioctl(struct drm_device *dev, void *data,
			struct drm_file *file_private)
{
	struct drm_syncobj_array *args = data;
	struct drm_syncobj **syncobjs;
	uint32_t i;
	int ret;

	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
		return -EOPNOTSUPP;

	if (args->pad != 0)
		return -EINVAL;

	if (args->count_handles == 0)
		return -EINVAL;

	ret = drm_syncobj_array_find(file_private,
				     u64_to_user_ptr(args->handles),
				     args->count_handles,
				     &syncobjs);
	if (ret < 0)
		return ret;

	for (i = 0; i < args->count_handles; i++)
		drm_syncobj_replace_fence(syncobjs[i], NULL);

	drm_syncobj_array_free(syncobjs, args->count_handles);

	return 0;
}

int
drm_syncobj_signal_ioctl(struct drm_device *dev, void *data,
			 struct drm_file *file_private)
{
	struct drm_syncobj_array *args = data;
	struct drm_syncobj **syncobjs;
	uint32_t i;
	int ret;

	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
		return -EOPNOTSUPP;

	if (args->pad != 0)
		return -EINVAL;

	if (args->count_handles == 0)
		return -EINVAL;

	ret = drm_syncobj_array_find(file_private,
				     u64_to_user_ptr(args->handles),
				     args->count_handles,
				     &syncobjs);
	if (ret < 0)
		return ret;

	for (i = 0; i < args->count_handles; i++)
		drm_syncobj_assign_null_handle(syncobjs[i]);

	drm_syncobj_array_free(syncobjs, args->count_handles);

	return ret;
}

int
drm_syncobj_timeline_signal_ioctl(struct drm_device *dev, void *data,
				  struct drm_file *file_private)
{
	struct drm_syncobj_timeline_array *args = data;
	struct drm_syncobj **syncobjs;
	struct dma_fence_chain **chains;
	uint64_t *points;
	uint32_t i, j;
	int ret;

	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE))
		return -EOPNOTSUPP;

	if (args->flags != 0)
		return -EINVAL;

	if (args->count_handles == 0)
		return -EINVAL;

	ret = drm_syncobj_array_find(file_private,
				     u64_to_user_ptr(args->handles),
				     args->count_handles,
				     &syncobjs);
	if (ret < 0)
		return ret;

	points = kmalloc_array(args->count_handles, sizeof(*points),
			       GFP_KERNEL);
	if (!points) {
		ret = -ENOMEM;
		goto out;
	}
	if (!u64_to_user_ptr(args->points)) {
		memset(points, 0, args->count_handles * sizeof(uint64_t));
	} else if (copy_from_user(points, u64_to_user_ptr(args->points),
				  sizeof(uint64_t) * args->count_handles)) {
		ret = -EFAULT;
		goto err_points;
	}

	chains = kmalloc_array(args->count_handles, sizeof(void *), GFP_KERNEL);
	if (!chains) {
		ret = -ENOMEM;
		goto err_points;
	}
	for (i = 0; i < args->count_handles; i++) {
		chains[i] = kzalloc(sizeof(struct dma_fence_chain), GFP_KERNEL);
		if (!chains[i]) {
			for (j = 0; j < i; j++)
				kfree(chains[j]);
			ret = -ENOMEM;
			goto err_chains;
		}
	}

	for (i = 0; i < args->count_handles; i++) {
		struct dma_fence *fence = dma_fence_get_stub();

		drm_syncobj_add_point(syncobjs[i], chains[i],
				      fence, points[i]);
		dma_fence_put(fence);
	}
err_chains:
	kfree(chains);
err_points:
	kfree(points);
out:
	drm_syncobj_array_free(syncobjs, args->count_handles);

	return ret;
}

int drm_syncobj_query_ioctl(struct drm_device *dev, void *data,
			    struct drm_file *file_private)
{
	struct drm_syncobj_timeline_array *args = data;
	struct drm_syncobj **syncobjs;
	uint64_t __user *points = u64_to_user_ptr(args->points);
	uint32_t i;
	int ret;

	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE))
		return -EOPNOTSUPP;

	if (args->flags & ~DRM_SYNCOBJ_QUERY_FLAGS_LAST_SUBMITTED)
		return -EINVAL;

	if (args->count_handles == 0)
		return -EINVAL;

	ret = drm_syncobj_array_find(file_private,
				     u64_to_user_ptr(args->handles),
				     args->count_handles,
				     &syncobjs);
	if (ret < 0)
		return ret;

	for (i = 0; i < args->count_handles; i++) {
		struct dma_fence_chain *chain;
		struct dma_fence *fence;
		uint64_t point;

		fence = drm_syncobj_fence_get(syncobjs[i]);
		chain = to_dma_fence_chain(fence);
		if (chain) {
			struct dma_fence *iter, *last_signaled =
				dma_fence_get(fence);

			if (args->flags &
			    DRM_SYNCOBJ_QUERY_FLAGS_LAST_SUBMITTED) {
				point = fence->seqno;
			} else {
				dma_fence_chain_for_each(iter, fence) {
					if (iter->context != fence->context) {
						dma_fence_put(iter);
						/* It is most likely that timeline has
						* unorder points. */
						break;
					}
					dma_fence_put(last_signaled);
					last_signaled = dma_fence_get(iter);
				}
				point = dma_fence_is_signaled(last_signaled) ?
					last_signaled->seqno :
					to_dma_fence_chain(last_signaled)->prev_seqno;
			}
			dma_fence_put(last_signaled);
		} else {
			point = 0;
		}
		dma_fence_put(fence);
		ret = copy_to_user(&points[i], &point, sizeof(uint64_t));
		ret = ret ? -EFAULT : 0;
		if (ret)
			break;
	}
	drm_syncobj_array_free(syncobjs, args->count_handles);

	return ret;
}