summaryrefslogtreecommitdiff
path: root/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c
blob: 711f8fd0dd454fcbde3f79643d874cf73c5527ae (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
// SPDX-License-Identifier: GPL-2.0 OR MIT
/**************************************************************************
 *
 * Copyright 2009-2015 VMware, Inc., Palo Alto, CA., USA
 *
 * 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, sub license, 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 NON-INFRINGEMENT. IN NO EVENT SHALL
 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS 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.
 *
 **************************************************************************/

#include "vmwgfx_drv.h"
#include <drm/vmwgfx_drm.h>
#include <drm/ttm/ttm_placement.h>
#include <drm/drmP.h>
#include "vmwgfx_resource_priv.h"
#include "vmwgfx_binding.h"

#define VMW_RES_EVICT_ERR_COUNT 10

struct vmw_resource *vmw_resource_reference(struct vmw_resource *res)
{
	kref_get(&res->kref);
	return res;
}

struct vmw_resource *
vmw_resource_reference_unless_doomed(struct vmw_resource *res)
{
	return kref_get_unless_zero(&res->kref) ? res : NULL;
}

/**
 * vmw_resource_release_id - release a resource id to the id manager.
 *
 * @res: Pointer to the resource.
 *
 * Release the resource id to the resource id manager and set it to -1
 */
void vmw_resource_release_id(struct vmw_resource *res)
{
	struct vmw_private *dev_priv = res->dev_priv;
	struct idr *idr = &dev_priv->res_idr[res->func->res_type];

	spin_lock(&dev_priv->resource_lock);
	if (res->id != -1)
		idr_remove(idr, res->id);
	res->id = -1;
	spin_unlock(&dev_priv->resource_lock);
}

static void vmw_resource_release(struct kref *kref)
{
	struct vmw_resource *res =
	    container_of(kref, struct vmw_resource, kref);
	struct vmw_private *dev_priv = res->dev_priv;
	int id;
	struct idr *idr = &dev_priv->res_idr[res->func->res_type];

	spin_lock(&dev_priv->resource_lock);
	list_del_init(&res->lru_head);
	spin_unlock(&dev_priv->resource_lock);
	if (res->backup) {
		struct ttm_buffer_object *bo = &res->backup->base;

		ttm_bo_reserve(bo, false, false, NULL);
		if (!list_empty(&res->mob_head) &&
		    res->func->unbind != NULL) {
			struct ttm_validate_buffer val_buf;

			val_buf.bo = bo;
			val_buf.num_shared = 0;
			res->func->unbind(res, false, &val_buf);
		}
		res->backup_dirty = false;
		list_del_init(&res->mob_head);
		ttm_bo_unreserve(bo);
		vmw_bo_unreference(&res->backup);
	}

	if (likely(res->hw_destroy != NULL)) {
		mutex_lock(&dev_priv->binding_mutex);
		vmw_binding_res_list_kill(&res->binding_head);
		mutex_unlock(&dev_priv->binding_mutex);
		res->hw_destroy(res);
	}

	id = res->id;
	if (res->res_free != NULL)
		res->res_free(res);
	else
		kfree(res);

	spin_lock(&dev_priv->resource_lock);
	if (id != -1)
		idr_remove(idr, id);
	spin_unlock(&dev_priv->resource_lock);
}

void vmw_resource_unreference(struct vmw_resource **p_res)
{
	struct vmw_resource *res = *p_res;

	*p_res = NULL;
	kref_put(&res->kref, vmw_resource_release);
}


/**
 * vmw_resource_alloc_id - release a resource id to the id manager.
 *
 * @res: Pointer to the resource.
 *
 * Allocate the lowest free resource from the resource manager, and set
 * @res->id to that id. Returns 0 on success and -ENOMEM on failure.
 */
int vmw_resource_alloc_id(struct vmw_resource *res)
{
	struct vmw_private *dev_priv = res->dev_priv;
	int ret;
	struct idr *idr = &dev_priv->res_idr[res->func->res_type];

	BUG_ON(res->id != -1);

	idr_preload(GFP_KERNEL);
	spin_lock(&dev_priv->resource_lock);

	ret = idr_alloc(idr, res, 1, 0, GFP_NOWAIT);
	if (ret >= 0)
		res->id = ret;

	spin_unlock(&dev_priv->resource_lock);
	idr_preload_end();
	return ret < 0 ? ret : 0;
}

/**
 * vmw_resource_init - initialize a struct vmw_resource
 *
 * @dev_priv:       Pointer to a device private struct.
 * @res:            The struct vmw_resource to initialize.
 * @obj_type:       Resource object type.
 * @delay_id:       Boolean whether to defer device id allocation until
 *                  the first validation.
 * @res_free:       Resource destructor.
 * @func:           Resource function table.
 */
int vmw_resource_init(struct vmw_private *dev_priv, struct vmw_resource *res,
		      bool delay_id,
		      void (*res_free) (struct vmw_resource *res),
		      const struct vmw_res_func *func)
{
	kref_init(&res->kref);
	res->hw_destroy = NULL;
	res->res_free = res_free;
	res->dev_priv = dev_priv;
	res->func = func;
	INIT_LIST_HEAD(&res->lru_head);
	INIT_LIST_HEAD(&res->mob_head);
	INIT_LIST_HEAD(&res->binding_head);
	res->id = -1;
	res->backup = NULL;
	res->backup_offset = 0;
	res->backup_dirty = false;
	res->res_dirty = false;
	if (delay_id)
		return 0;
	else
		return vmw_resource_alloc_id(res);
}


/**
 * vmw_user_resource_lookup_handle - lookup a struct resource from a
 * TTM user-space handle and perform basic type checks
 *
 * @dev_priv:     Pointer to a device private struct
 * @tfile:        Pointer to a struct ttm_object_file identifying the caller
 * @handle:       The TTM user-space handle
 * @converter:    Pointer to an object describing the resource type
 * @p_res:        On successful return the location pointed to will contain
 *                a pointer to a refcounted struct vmw_resource.
 *
 * If the handle can't be found or is associated with an incorrect resource
 * type, -EINVAL will be returned.
 */
int vmw_user_resource_lookup_handle(struct vmw_private *dev_priv,
				    struct ttm_object_file *tfile,
				    uint32_t handle,
				    const struct vmw_user_resource_conv
				    *converter,
				    struct vmw_resource **p_res)
{
	struct ttm_base_object *base;
	struct vmw_resource *res;
	int ret = -EINVAL;

	base = ttm_base_object_lookup(tfile, handle);
	if (unlikely(base == NULL))
		return -EINVAL;

	if (unlikely(ttm_base_object_type(base) != converter->object_type))
		goto out_bad_resource;

	res = converter->base_obj_to_res(base);
	kref_get(&res->kref);

	*p_res = res;
	ret = 0;

out_bad_resource:
	ttm_base_object_unref(&base);

	return ret;
}

/**
 * vmw_user_resource_lookup_handle - lookup a struct resource from a
 * TTM user-space handle and perform basic type checks
 *
 * @dev_priv:     Pointer to a device private struct
 * @tfile:        Pointer to a struct ttm_object_file identifying the caller
 * @handle:       The TTM user-space handle
 * @converter:    Pointer to an object describing the resource type
 * @p_res:        On successful return the location pointed to will contain
 *                a pointer to a refcounted struct vmw_resource.
 *
 * If the handle can't be found or is associated with an incorrect resource
 * type, -EINVAL will be returned.
 */
struct vmw_resource *
vmw_user_resource_noref_lookup_handle(struct vmw_private *dev_priv,
				      struct ttm_object_file *tfile,
				      uint32_t handle,
				      const struct vmw_user_resource_conv
				      *converter)
{
	struct ttm_base_object *base;

	base = ttm_base_object_noref_lookup(tfile, handle);
	if (!base)
		return ERR_PTR(-ESRCH);

	if (unlikely(ttm_base_object_type(base) != converter->object_type)) {
		ttm_base_object_noref_release();
		return ERR_PTR(-EINVAL);
	}

	return converter->base_obj_to_res(base);
}

/**
 * Helper function that looks either a surface or bo.
 *
 * The pointer this pointed at by out_surf and out_buf needs to be null.
 */
int vmw_user_lookup_handle(struct vmw_private *dev_priv,
			   struct ttm_object_file *tfile,
			   uint32_t handle,
			   struct vmw_surface **out_surf,
			   struct vmw_buffer_object **out_buf)
{
	struct vmw_resource *res;
	int ret;

	BUG_ON(*out_surf || *out_buf);

	ret = vmw_user_resource_lookup_handle(dev_priv, tfile, handle,
					      user_surface_converter,
					      &res);
	if (!ret) {
		*out_surf = vmw_res_to_srf(res);
		return 0;
	}

	*out_surf = NULL;
	ret = vmw_user_bo_lookup(tfile, handle, out_buf, NULL);
	return ret;
}

/**
 * vmw_resource_buf_alloc - Allocate a backup buffer for a resource.
 *
 * @res:            The resource for which to allocate a backup buffer.
 * @interruptible:  Whether any sleeps during allocation should be
 *                  performed while interruptible.
 */
static int vmw_resource_buf_alloc(struct vmw_resource *res,
				  bool interruptible)
{
	unsigned long size =
		(res->backup_size + PAGE_SIZE - 1) & PAGE_MASK;
	struct vmw_buffer_object *backup;
	int ret;

	if (likely(res->backup)) {
		BUG_ON(res->backup->base.num_pages * PAGE_SIZE < size);
		return 0;
	}

	backup = kzalloc(sizeof(*backup), GFP_KERNEL);
	if (unlikely(!backup))
		return -ENOMEM;

	ret = vmw_bo_init(res->dev_priv, backup, res->backup_size,
			      res->func->backup_placement,
			      interruptible,
			      &vmw_bo_bo_free);
	if (unlikely(ret != 0))
		goto out_no_bo;

	res->backup = backup;

out_no_bo:
	return ret;
}

/**
 * vmw_resource_do_validate - Make a resource up-to-date and visible
 *                            to the device.
 *
 * @res:            The resource to make visible to the device.
 * @val_buf:        Information about a buffer possibly
 *                  containing backup data if a bind operation is needed.
 *
 * On hardware resource shortage, this function returns -EBUSY and
 * should be retried once resources have been freed up.
 */
static int vmw_resource_do_validate(struct vmw_resource *res,
				    struct ttm_validate_buffer *val_buf)
{
	int ret = 0;
	const struct vmw_res_func *func = res->func;

	if (unlikely(res->id == -1)) {
		ret = func->create(res);
		if (unlikely(ret != 0))
			return ret;
	}

	if (func->bind &&
	    ((func->needs_backup && list_empty(&res->mob_head) &&
	      val_buf->bo != NULL) ||
	     (!func->needs_backup && val_buf->bo != NULL))) {
		ret = func->bind(res, val_buf);
		if (unlikely(ret != 0))
			goto out_bind_failed;
		if (func->needs_backup)
			list_add_tail(&res->mob_head, &res->backup->res_list);
	}

	return 0;

out_bind_failed:
	func->destroy(res);

	return ret;
}

/**
 * vmw_resource_unreserve - Unreserve a resource previously reserved for
 * command submission.
 *
 * @res:               Pointer to the struct vmw_resource to unreserve.
 * @dirty_set:         Change dirty status of the resource.
 * @dirty:             When changing dirty status indicates the new status.
 * @switch_backup:     Backup buffer has been switched.
 * @new_backup:        Pointer to new backup buffer if command submission
 *                     switched. May be NULL.
 * @new_backup_offset: New backup offset if @switch_backup is true.
 *
 * Currently unreserving a resource means putting it back on the device's
 * resource lru list, so that it can be evicted if necessary.
 */
void vmw_resource_unreserve(struct vmw_resource *res,
			    bool dirty_set,
			    bool dirty,
			    bool switch_backup,
			    struct vmw_buffer_object *new_backup,
			    unsigned long new_backup_offset)
{
	struct vmw_private *dev_priv = res->dev_priv;

	if (!list_empty(&res->lru_head))
		return;

	if (switch_backup && new_backup != res->backup) {
		if (res->backup) {
			lockdep_assert_held(&res->backup->base.resv->lock.base);
			list_del_init(&res->mob_head);
			vmw_bo_unreference(&res->backup);
		}

		if (new_backup) {
			res->backup = vmw_bo_reference(new_backup);
			lockdep_assert_held(&new_backup->base.resv->lock.base);
			list_add_tail(&res->mob_head, &new_backup->res_list);
		} else {
			res->backup = NULL;
		}
	}
	if (switch_backup)
		res->backup_offset = new_backup_offset;

	if (dirty_set)
		res->res_dirty = dirty;

	if (!res->func->may_evict || res->id == -1 || res->pin_count)
		return;

	spin_lock(&dev_priv->resource_lock);
	list_add_tail(&res->lru_head,
		      &res->dev_priv->res_lru[res->func->res_type]);
	spin_unlock(&dev_priv->resource_lock);
}

/**
 * vmw_resource_check_buffer - Check whether a backup buffer is needed
 *                             for a resource and in that case, allocate
 *                             one, reserve and validate it.
 *
 * @ticket:         The ww aqcquire context to use, or NULL if trylocking.
 * @res:            The resource for which to allocate a backup buffer.
 * @interruptible:  Whether any sleeps during allocation should be
 *                  performed while interruptible.
 * @val_buf:        On successful return contains data about the
 *                  reserved and validated backup buffer.
 */
static int
vmw_resource_check_buffer(struct ww_acquire_ctx *ticket,
			  struct vmw_resource *res,
			  bool interruptible,
			  struct ttm_validate_buffer *val_buf)
{
	struct ttm_operation_ctx ctx = { true, false };
	struct list_head val_list;
	bool backup_dirty = false;
	int ret;

	if (unlikely(res->backup == NULL)) {
		ret = vmw_resource_buf_alloc(res, interruptible);
		if (unlikely(ret != 0))
			return ret;
	}

	INIT_LIST_HEAD(&val_list);
	ttm_bo_get(&res->backup->base);
	val_buf->bo = &res->backup->base;
	val_buf->num_shared = 0;
	list_add_tail(&val_buf->head, &val_list);
	ret = ttm_eu_reserve_buffers(ticket, &val_list, interruptible, NULL);
	if (unlikely(ret != 0))
		goto out_no_reserve;

	if (res->func->needs_backup && list_empty(&res->mob_head))
		return 0;

	backup_dirty = res->backup_dirty;
	ret = ttm_bo_validate(&res->backup->base,
			      res->func->backup_placement,
			      &ctx);

	if (unlikely(ret != 0))
		goto out_no_validate;

	return 0;

out_no_validate:
	ttm_eu_backoff_reservation(ticket, &val_list);
out_no_reserve:
	ttm_bo_put(val_buf->bo);
	val_buf->bo = NULL;
	if (backup_dirty)
		vmw_bo_unreference(&res->backup);

	return ret;
}

/**
 * vmw_resource_reserve - Reserve a resource for command submission
 *
 * @res:            The resource to reserve.
 *
 * This function takes the resource off the LRU list and make sure
 * a backup buffer is present for guest-backed resources. However,
 * the buffer may not be bound to the resource at this point.
 *
 */
int vmw_resource_reserve(struct vmw_resource *res, bool interruptible,
			 bool no_backup)
{
	struct vmw_private *dev_priv = res->dev_priv;
	int ret;

	spin_lock(&dev_priv->resource_lock);
	list_del_init(&res->lru_head);
	spin_unlock(&dev_priv->resource_lock);

	if (res->func->needs_backup && res->backup == NULL &&
	    !no_backup) {
		ret = vmw_resource_buf_alloc(res, interruptible);
		if (unlikely(ret != 0)) {
			DRM_ERROR("Failed to allocate a backup buffer "
				  "of size %lu. bytes\n",
				  (unsigned long) res->backup_size);
			return ret;
		}
	}

	return 0;
}

/**
 * vmw_resource_backoff_reservation - Unreserve and unreference a
 *                                    backup buffer
 *.
 * @ticket:         The ww acquire ctx used for reservation.
 * @val_buf:        Backup buffer information.
 */
static void
vmw_resource_backoff_reservation(struct ww_acquire_ctx *ticket,
				 struct ttm_validate_buffer *val_buf)
{
	struct list_head val_list;

	if (likely(val_buf->bo == NULL))
		return;

	INIT_LIST_HEAD(&val_list);
	list_add_tail(&val_buf->head, &val_list);
	ttm_eu_backoff_reservation(ticket, &val_list);
	ttm_bo_put(val_buf->bo);
	val_buf->bo = NULL;
}

/**
 * vmw_resource_do_evict - Evict a resource, and transfer its data
 *                         to a backup buffer.
 *
 * @ticket:         The ww acquire ticket to use, or NULL if trylocking.
 * @res:            The resource to evict.
 * @interruptible:  Whether to wait interruptible.
 */
static int vmw_resource_do_evict(struct ww_acquire_ctx *ticket,
				 struct vmw_resource *res, bool interruptible)
{
	struct ttm_validate_buffer val_buf;
	const struct vmw_res_func *func = res->func;
	int ret;

	BUG_ON(!func->may_evict);

	val_buf.bo = NULL;
	val_buf.num_shared = 0;
	ret = vmw_resource_check_buffer(ticket, res, interruptible, &val_buf);
	if (unlikely(ret != 0))
		return ret;

	if (unlikely(func->unbind != NULL &&
		     (!func->needs_backup || !list_empty(&res->mob_head)))) {
		ret = func->unbind(res, res->res_dirty, &val_buf);
		if (unlikely(ret != 0))
			goto out_no_unbind;
		list_del_init(&res->mob_head);
	}
	ret = func->destroy(res);
	res->backup_dirty = true;
	res->res_dirty = false;
out_no_unbind:
	vmw_resource_backoff_reservation(ticket, &val_buf);

	return ret;
}


/**
 * vmw_resource_validate - Make a resource up-to-date and visible
 *                         to the device.
 * @res: The resource to make visible to the device.
 * @intr: Perform waits interruptible if possible.
 *
 * On succesful return, any backup DMA buffer pointed to by @res->backup will
 * be reserved and validated.
 * On hardware resource shortage, this function will repeatedly evict
 * resources of the same type until the validation succeeds.
 *
 * Return: Zero on success, -ERESTARTSYS if interrupted, negative error code
 * on failure.
 */
int vmw_resource_validate(struct vmw_resource *res, bool intr)
{
	int ret;
	struct vmw_resource *evict_res;
	struct vmw_private *dev_priv = res->dev_priv;
	struct list_head *lru_list = &dev_priv->res_lru[res->func->res_type];
	struct ttm_validate_buffer val_buf;
	unsigned err_count = 0;

	if (!res->func->create)
		return 0;

	val_buf.bo = NULL;
	val_buf.num_shared = 0;
	if (res->backup)
		val_buf.bo = &res->backup->base;
	do {
		ret = vmw_resource_do_validate(res, &val_buf);
		if (likely(ret != -EBUSY))
			break;

		spin_lock(&dev_priv->resource_lock);
		if (list_empty(lru_list) || !res->func->may_evict) {
			DRM_ERROR("Out of device device resources "
				  "for %s.\n", res->func->type_name);
			ret = -EBUSY;
			spin_unlock(&dev_priv->resource_lock);
			break;
		}

		evict_res = vmw_resource_reference
			(list_first_entry(lru_list, struct vmw_resource,
					  lru_head));
		list_del_init(&evict_res->lru_head);

		spin_unlock(&dev_priv->resource_lock);

		/* Trylock backup buffers with a NULL ticket. */
		ret = vmw_resource_do_evict(NULL, evict_res, intr);
		if (unlikely(ret != 0)) {
			spin_lock(&dev_priv->resource_lock);
			list_add_tail(&evict_res->lru_head, lru_list);
			spin_unlock(&dev_priv->resource_lock);
			if (ret == -ERESTARTSYS ||
			    ++err_count > VMW_RES_EVICT_ERR_COUNT) {
				vmw_resource_unreference(&evict_res);
				goto out_no_validate;
			}
		}

		vmw_resource_unreference(&evict_res);
	} while (1);

	if (unlikely(ret != 0))
		goto out_no_validate;
	else if (!res->func->needs_backup && res->backup) {
		list_del_init(&res->mob_head);
		vmw_bo_unreference(&res->backup);
	}

	return 0;

out_no_validate:
	return ret;
}


/**
 * vmw_resource_unbind_list
 *
 * @vbo: Pointer to the current backing MOB.
 *
 * Evicts the Guest Backed hardware resource if the backup
 * buffer is being moved out of MOB memory.
 * Note that this function will not race with the resource
 * validation code, since resource validation and eviction
 * both require the backup buffer to be reserved.
 */
void vmw_resource_unbind_list(struct vmw_buffer_object *vbo)
{

	struct vmw_resource *res, *next;
	struct ttm_validate_buffer val_buf = {
		.bo = &vbo->base,
		.num_shared = 0
	};

	lockdep_assert_held(&vbo->base.resv->lock.base);
	list_for_each_entry_safe(res, next, &vbo->res_list, mob_head) {
		if (!res->func->unbind)
			continue;

		(void) res->func->unbind(res, res->res_dirty, &val_buf);
		res->backup_dirty = true;
		res->res_dirty = false;
		list_del_init(&res->mob_head);
	}

	(void) ttm_bo_wait(&vbo->base, false, false);
}


/**
 * vmw_query_readback_all - Read back cached query states
 *
 * @dx_query_mob: Buffer containing the DX query MOB
 *
 * Read back cached states from the device if they exist.  This function
 * assumings binding_mutex is held.
 */
int vmw_query_readback_all(struct vmw_buffer_object *dx_query_mob)
{
	struct vmw_resource *dx_query_ctx;
	struct vmw_private *dev_priv;
	struct {
		SVGA3dCmdHeader header;
		SVGA3dCmdDXReadbackAllQuery body;
	} *cmd;


	/* No query bound, so do nothing */
	if (!dx_query_mob || !dx_query_mob->dx_query_ctx)
		return 0;

	dx_query_ctx = dx_query_mob->dx_query_ctx;
	dev_priv     = dx_query_ctx->dev_priv;

	cmd = VMW_FIFO_RESERVE_DX(dev_priv, sizeof(*cmd), dx_query_ctx->id);
	if (unlikely(cmd == NULL))
		return -ENOMEM;

	cmd->header.id   = SVGA_3D_CMD_DX_READBACK_ALL_QUERY;
	cmd->header.size = sizeof(cmd->body);
	cmd->body.cid    = dx_query_ctx->id;

	vmw_fifo_commit(dev_priv, sizeof(*cmd));

	/* Triggers a rebind the next time affected context is bound */
	dx_query_mob->dx_query_ctx = NULL;

	return 0;
}



/**
 * vmw_query_move_notify - Read back cached query states
 *
 * @bo: The TTM buffer object about to move.
 * @mem: The memory region @bo is moving to.
 *
 * Called before the query MOB is swapped out to read back cached query
 * states from the device.
 */
void vmw_query_move_notify(struct ttm_buffer_object *bo,
			   struct ttm_mem_reg *mem)
{
	struct vmw_buffer_object *dx_query_mob;
	struct ttm_bo_device *bdev = bo->bdev;
	struct vmw_private *dev_priv;


	dev_priv = container_of(bdev, struct vmw_private, bdev);

	mutex_lock(&dev_priv->binding_mutex);

	dx_query_mob = container_of(bo, struct vmw_buffer_object, base);
	if (mem == NULL || !dx_query_mob || !dx_query_mob->dx_query_ctx) {
		mutex_unlock(&dev_priv->binding_mutex);
		return;
	}

	/* If BO is being moved from MOB to system memory */
	if (mem->mem_type == TTM_PL_SYSTEM && bo->mem.mem_type == VMW_PL_MOB) {
		struct vmw_fence_obj *fence;

		(void) vmw_query_readback_all(dx_query_mob);
		mutex_unlock(&dev_priv->binding_mutex);

		/* Create a fence and attach the BO to it */
		(void) vmw_execbuf_fence_commands(NULL, dev_priv, &fence, NULL);
		vmw_bo_fence_single(bo, fence);

		if (fence != NULL)
			vmw_fence_obj_unreference(&fence);

		(void) ttm_bo_wait(bo, false, false);
	} else
		mutex_unlock(&dev_priv->binding_mutex);

}

/**
 * vmw_resource_needs_backup - Return whether a resource needs a backup buffer.
 *
 * @res:            The resource being queried.
 */
bool vmw_resource_needs_backup(const struct vmw_resource *res)
{
	return res->func->needs_backup;
}

/**
 * vmw_resource_evict_type - Evict all resources of a specific type
 *
 * @dev_priv:       Pointer to a device private struct
 * @type:           The resource type to evict
 *
 * To avoid thrashing starvation or as part of the hibernation sequence,
 * try to evict all evictable resources of a specific type.
 */
static void vmw_resource_evict_type(struct vmw_private *dev_priv,
				    enum vmw_res_type type)
{
	struct list_head *lru_list = &dev_priv->res_lru[type];
	struct vmw_resource *evict_res;
	unsigned err_count = 0;
	int ret;
	struct ww_acquire_ctx ticket;

	do {
		spin_lock(&dev_priv->resource_lock);

		if (list_empty(lru_list))
			goto out_unlock;

		evict_res = vmw_resource_reference(
			list_first_entry(lru_list, struct vmw_resource,
					 lru_head));
		list_del_init(&evict_res->lru_head);
		spin_unlock(&dev_priv->resource_lock);

		/* Wait lock backup buffers with a ticket. */
		ret = vmw_resource_do_evict(&ticket, evict_res, false);
		if (unlikely(ret != 0)) {
			spin_lock(&dev_priv->resource_lock);
			list_add_tail(&evict_res->lru_head, lru_list);
			spin_unlock(&dev_priv->resource_lock);
			if (++err_count > VMW_RES_EVICT_ERR_COUNT) {
				vmw_resource_unreference(&evict_res);
				return;
			}
		}

		vmw_resource_unreference(&evict_res);
	} while (1);

out_unlock:
	spin_unlock(&dev_priv->resource_lock);
}

/**
 * vmw_resource_evict_all - Evict all evictable resources
 *
 * @dev_priv:       Pointer to a device private struct
 *
 * To avoid thrashing starvation or as part of the hibernation sequence,
 * evict all evictable resources. In particular this means that all
 * guest-backed resources that are registered with the device are
 * evicted and the OTable becomes clean.
 */
void vmw_resource_evict_all(struct vmw_private *dev_priv)
{
	enum vmw_res_type type;

	mutex_lock(&dev_priv->cmdbuf_mutex);

	for (type = 0; type < vmw_res_max; ++type)
		vmw_resource_evict_type(dev_priv, type);

	mutex_unlock(&dev_priv->cmdbuf_mutex);
}

/**
 * vmw_resource_pin - Add a pin reference on a resource
 *
 * @res: The resource to add a pin reference on
 *
 * This function adds a pin reference, and if needed validates the resource.
 * Having a pin reference means that the resource can never be evicted, and
 * its id will never change as long as there is a pin reference.
 * This function returns 0 on success and a negative error code on failure.
 */
int vmw_resource_pin(struct vmw_resource *res, bool interruptible)
{
	struct ttm_operation_ctx ctx = { interruptible, false };
	struct vmw_private *dev_priv = res->dev_priv;
	int ret;

	ttm_write_lock(&dev_priv->reservation_sem, interruptible);
	mutex_lock(&dev_priv->cmdbuf_mutex);
	ret = vmw_resource_reserve(res, interruptible, false);
	if (ret)
		goto out_no_reserve;

	if (res->pin_count == 0) {
		struct vmw_buffer_object *vbo = NULL;

		if (res->backup) {
			vbo = res->backup;

			ttm_bo_reserve(&vbo->base, interruptible, false, NULL);
			if (!vbo->pin_count) {
				ret = ttm_bo_validate
					(&vbo->base,
					 res->func->backup_placement,
					 &ctx);
				if (ret) {
					ttm_bo_unreserve(&vbo->base);
					goto out_no_validate;
				}
			}

			/* Do we really need to pin the MOB as well? */
			vmw_bo_pin_reserved(vbo, true);
		}
		ret = vmw_resource_validate(res, interruptible);
		if (vbo)
			ttm_bo_unreserve(&vbo->base);
		if (ret)
			goto out_no_validate;
	}
	res->pin_count++;

out_no_validate:
	vmw_resource_unreserve(res, false, false, false, NULL, 0UL);
out_no_reserve:
	mutex_unlock(&dev_priv->cmdbuf_mutex);
	ttm_write_unlock(&dev_priv->reservation_sem);

	return ret;
}

/**
 * vmw_resource_unpin - Remove a pin reference from a resource
 *
 * @res: The resource to remove a pin reference from
 *
 * Having a pin reference means that the resource can never be evicted, and
 * its id will never change as long as there is a pin reference.
 */
void vmw_resource_unpin(struct vmw_resource *res)
{
	struct vmw_private *dev_priv = res->dev_priv;
	int ret;

	(void) ttm_read_lock(&dev_priv->reservation_sem, false);
	mutex_lock(&dev_priv->cmdbuf_mutex);

	ret = vmw_resource_reserve(res, false, true);
	WARN_ON(ret);

	WARN_ON(res->pin_count == 0);
	if (--res->pin_count == 0 && res->backup) {
		struct vmw_buffer_object *vbo = res->backup;

		(void) ttm_bo_reserve(&vbo->base, false, false, NULL);
		vmw_bo_pin_reserved(vbo, false);
		ttm_bo_unreserve(&vbo->base);
	}

	vmw_resource_unreserve(res, false, false, false, NULL, 0UL);

	mutex_unlock(&dev_priv->cmdbuf_mutex);
	ttm_read_unlock(&dev_priv->reservation_sem);
}

/**
 * vmw_res_type - Return the resource type
 *
 * @res: Pointer to the resource
 */
enum vmw_res_type vmw_res_type(const struct vmw_resource *res)
{
	return res->func->res_type;
}