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
#[cfg(feature = "trace")]
use crate::device::trace::Command as TraceCommand;
use crate::{
    api_log,
    command::{clear_texture, CommandEncoderError},
    conv,
    device::{Device, DeviceError, MissingDownlevelFlags},
    global::Global,
    id::{BufferId, CommandEncoderId, TextureId},
    init_tracker::{
        has_copy_partial_init_tracker_coverage, MemoryInitKind, TextureInitRange,
        TextureInitTrackerAction,
    },
    resource::{
        DestroyedResourceError, InvalidResourceError, MissingBufferUsageError,
        MissingTextureUsageError, ParentDevice, Texture, TextureErrorDimension,
    },
    snatch::SnatchGuard,
    track::TextureSelector,
};

use arrayvec::ArrayVec;
use thiserror::Error;
use wgt::{BufferAddress, BufferUsages, Extent3d, TextureUsages};

use std::sync::Arc;

use super::{ClearError, CommandBufferMutable};

pub type TexelCopyBufferInfo = wgt::TexelCopyBufferInfo<BufferId>;
pub type TexelCopyTextureInfo = wgt::TexelCopyTextureInfo<TextureId>;
pub type CopyExternalImageDestInfo = wgt::CopyExternalImageDestInfo<TextureId>;

#[deprecated(
    since = "24.0.0",
    note = "This has been renamed to `TexelCopyBufferInfo`, and will be removed in 25.0.0."
)]
pub type ImageCopyBuffer = wgt::TexelCopyBufferInfo<BufferId>;

#[deprecated(
    since = "24.0.0",
    note = "This has been renamed to `TexelCopyTextureInfo`, and will be removed in 25.0.0."
)]
pub type ImageCopyTexture = wgt::TexelCopyTextureInfo<TextureId>;

#[deprecated(
    since = "24.0.0",
    note = "This has been renamed to `TexelCopyTextureSourceInfo`, and will be removed in 25.0.0."
)]
pub type ImageCopyTextureTagged = wgt::CopyExternalImageDestInfo<TextureId>;

#[derive(Clone, Copy, Debug)]
pub enum CopySide {
    Source,
    Destination,
}

/// Error encountered while attempting a data transfer.
#[derive(Clone, Debug, Error)]
#[non_exhaustive]
pub enum TransferError {
    #[error("Source and destination cannot be the same buffer")]
    SameSourceDestinationBuffer,
    #[error(transparent)]
    MissingBufferUsage(#[from] MissingBufferUsageError),
    #[error(transparent)]
    MissingTextureUsage(#[from] MissingTextureUsageError),
    #[error("Copy of {start_offset}..{end_offset} would end up overrunning the bounds of the {side:?} buffer of size {buffer_size}")]
    BufferOverrun {
        start_offset: BufferAddress,
        end_offset: BufferAddress,
        buffer_size: BufferAddress,
        side: CopySide,
    },
    #[error("Copy of {dimension:?} {start_offset}..{end_offset} would end up overrunning the bounds of the {side:?} texture of {dimension:?} size {texture_size}")]
    TextureOverrun {
        start_offset: u32,
        end_offset: u32,
        texture_size: u32,
        dimension: TextureErrorDimension,
        side: CopySide,
    },
    #[error("Unable to select texture aspect {aspect:?} from format {format:?}")]
    InvalidTextureAspect {
        format: wgt::TextureFormat,
        aspect: wgt::TextureAspect,
    },
    #[error("Unable to select texture mip level {level} out of {total}")]
    InvalidTextureMipLevel { level: u32, total: u32 },
    #[error("Texture dimension must be 2D when copying from an external texture")]
    InvalidDimensionExternal,
    #[error("Buffer offset {0} is not aligned to block size or `COPY_BUFFER_ALIGNMENT`")]
    UnalignedBufferOffset(BufferAddress),
    #[error("Copy size {0} does not respect `COPY_BUFFER_ALIGNMENT`")]
    UnalignedCopySize(BufferAddress),
    #[error("Copy width is not a multiple of block width")]
    UnalignedCopyWidth,
    #[error("Copy height is not a multiple of block height")]
    UnalignedCopyHeight,
    #[error("Copy origin's x component is not a multiple of block width")]
    UnalignedCopyOriginX,
    #[error("Copy origin's y component is not a multiple of block height")]
    UnalignedCopyOriginY,
    #[error("Bytes per row does not respect `COPY_BYTES_PER_ROW_ALIGNMENT`")]
    UnalignedBytesPerRow,
    #[error("Number of bytes per row needs to be specified since more than one row is copied")]
    UnspecifiedBytesPerRow,
    #[error("Number of rows per image needs to be specified since more than one image is copied")]
    UnspecifiedRowsPerImage,
    #[error("Number of bytes per row is less than the number of bytes in a complete row")]
    InvalidBytesPerRow,
    #[error("Number of rows per image is invalid")]
    InvalidRowsPerImage,
    #[error("Copy source aspects must refer to all aspects of the source texture format")]
    CopySrcMissingAspects,
    #[error(
        "Copy destination aspects must refer to all aspects of the destination texture format"
    )]
    CopyDstMissingAspects,
    #[error("Copy aspect must refer to a single aspect of texture format")]
    CopyAspectNotOne,
    #[error("Copying from textures with format {format:?} and aspect {aspect:?} is forbidden")]
    CopyFromForbiddenTextureFormat {
        format: wgt::TextureFormat,
        aspect: wgt::TextureAspect,
    },
    #[error("Copying to textures with format {format:?} and aspect {aspect:?} is forbidden")]
    CopyToForbiddenTextureFormat {
        format: wgt::TextureFormat,
        aspect: wgt::TextureAspect,
    },
    #[error(
        "Copying to textures with format {0:?} is forbidden when copying from external texture"
    )]
    ExternalCopyToForbiddenTextureFormat(wgt::TextureFormat),
    #[error(
        "Source format ({src_format:?}) and destination format ({dst_format:?}) are not copy-compatible (they may only differ in srgb-ness)"
    )]
    TextureFormatsNotCopyCompatible {
        src_format: wgt::TextureFormat,
        dst_format: wgt::TextureFormat,
    },
    #[error(transparent)]
    MemoryInitFailure(#[from] ClearError),
    #[error("Cannot encode this copy because of a missing downelevel flag")]
    MissingDownlevelFlags(#[from] MissingDownlevelFlags),
    #[error("Source texture sample count must be 1, got {sample_count}")]
    InvalidSampleCount { sample_count: u32 },
    #[error("Requested mip level {requested} does no exist (count: {count})")]
    InvalidMipLevel { requested: u32, count: u32 },
}

/// Error encountered while attempting to do a copy on a command encoder.
#[derive(Clone, Debug, Error)]
#[non_exhaustive]
pub enum CopyError {
    #[error(transparent)]
    Encoder(#[from] CommandEncoderError),
    #[error("Copy error")]
    Transfer(#[from] TransferError),
    #[error(transparent)]
    DestroyedResource(#[from] DestroyedResourceError),
    #[error(transparent)]
    InvalidResource(#[from] InvalidResourceError),
}

impl From<DeviceError> for CopyError {
    fn from(err: DeviceError) -> Self {
        CopyError::Encoder(CommandEncoderError::Device(err))
    }
}

pub(crate) fn extract_texture_selector<T>(
    copy_texture: &wgt::TexelCopyTextureInfo<T>,
    copy_size: &Extent3d,
    texture: &Texture,
) -> Result<(TextureSelector, hal::TextureCopyBase), TransferError> {
    let format = texture.desc.format;
    let copy_aspect = hal::FormatAspects::new(format, copy_texture.aspect);
    if copy_aspect.is_empty() {
        return Err(TransferError::InvalidTextureAspect {
            format,
            aspect: copy_texture.aspect,
        });
    }

    let (layers, origin_z) = match texture.desc.dimension {
        wgt::TextureDimension::D1 => (0..1, 0),
        wgt::TextureDimension::D2 => (
            copy_texture.origin.z..copy_texture.origin.z + copy_size.depth_or_array_layers,
            0,
        ),
        wgt::TextureDimension::D3 => (0..1, copy_texture.origin.z),
    };
    let base = hal::TextureCopyBase {
        origin: wgt::Origin3d {
            x: copy_texture.origin.x,
            y: copy_texture.origin.y,
            z: origin_z,
        },
        // this value will be incremented per copied layer
        array_layer: layers.start,
        mip_level: copy_texture.mip_level,
        aspect: copy_aspect,
    };
    let selector = TextureSelector {
        mips: copy_texture.mip_level..copy_texture.mip_level + 1,
        layers,
    };

    Ok((selector, base))
}

/// WebGPU's [validating linear texture data][vltd] algorithm.
///
/// Copied with some modifications from WebGPU standard.
///
/// If successful, returns a pair `(bytes, stride)`, where:
/// - `bytes` is the number of buffer bytes required for this copy, and
/// - `stride` number of bytes between array layers.
///
/// [vltd]: https://gpuweb.github.io/gpuweb/#abstract-opdef-validating-linear-texture-data
pub(crate) fn validate_linear_texture_data(
    layout: &wgt::TexelCopyBufferLayout,
    format: wgt::TextureFormat,
    aspect: wgt::TextureAspect,
    buffer_size: BufferAddress,
    buffer_side: CopySide,
    copy_size: &Extent3d,
    need_copy_aligned_rows: bool,
) -> Result<(BufferAddress, BufferAddress), TransferError> {
    // Convert all inputs to BufferAddress (u64) to avoid some of the overflow issues
    // Note: u64 is not always enough to prevent overflow, especially when multiplying
    // something with a potentially large depth value, so it is preferable to validate
    // the copy size before calling this function (for example via `validate_texture_copy_range`).
    let copy_width = copy_size.width as BufferAddress;
    let copy_height = copy_size.height as BufferAddress;
    let depth_or_array_layers = copy_size.depth_or_array_layers as BufferAddress;

    let offset = layout.offset;

    let block_size = format.block_copy_size(Some(aspect)).unwrap() as BufferAddress;
    let (block_width, block_height) = format.block_dimensions();
    let block_width = block_width as BufferAddress;
    let block_height = block_height as BufferAddress;

    if copy_width % block_width != 0 {
        return Err(TransferError::UnalignedCopyWidth);
    }
    if copy_height % block_height != 0 {
        return Err(TransferError::UnalignedCopyHeight);
    }

    let width_in_blocks = copy_width / block_width;
    let height_in_blocks = copy_height / block_height;

    let bytes_in_last_row = width_in_blocks * block_size;

    let bytes_per_row = if let Some(bytes_per_row) = layout.bytes_per_row {
        let bytes_per_row = bytes_per_row as BufferAddress;
        if bytes_per_row < bytes_in_last_row {
            return Err(TransferError::InvalidBytesPerRow);
        }
        bytes_per_row
    } else {
        if depth_or_array_layers > 1 || height_in_blocks > 1 {
            return Err(TransferError::UnspecifiedBytesPerRow);
        }
        0
    };
    let rows_per_image = if let Some(rows_per_image) = layout.rows_per_image {
        let rows_per_image = rows_per_image as BufferAddress;
        if rows_per_image < height_in_blocks {
            return Err(TransferError::InvalidRowsPerImage);
        }
        rows_per_image
    } else {
        if depth_or_array_layers > 1 {
            return Err(TransferError::UnspecifiedRowsPerImage);
        }
        0
    };

    if need_copy_aligned_rows {
        let bytes_per_row_alignment = wgt::COPY_BYTES_PER_ROW_ALIGNMENT as BufferAddress;

        let mut offset_alignment = block_size;
        if format.is_depth_stencil_format() {
            offset_alignment = 4
        }
        if offset % offset_alignment != 0 {
            return Err(TransferError::UnalignedBufferOffset(offset));
        }

        if bytes_per_row % bytes_per_row_alignment != 0 {
            return Err(TransferError::UnalignedBytesPerRow);
        }
    }

    let bytes_per_image = bytes_per_row * rows_per_image;

    let required_bytes_in_copy = if depth_or_array_layers == 0 {
        0
    } else {
        let mut required_bytes_in_copy = bytes_per_image * (depth_or_array_layers - 1);
        if height_in_blocks > 0 {
            required_bytes_in_copy += bytes_per_row * (height_in_blocks - 1) + bytes_in_last_row;
        }
        required_bytes_in_copy
    };

    if offset + required_bytes_in_copy > buffer_size {
        return Err(TransferError::BufferOverrun {
            start_offset: offset,
            end_offset: offset + required_bytes_in_copy,
            buffer_size,
            side: buffer_side,
        });
    }

    Ok((required_bytes_in_copy, bytes_per_image))
}

/// WebGPU's [validating texture copy range][vtcr] algorithm.
///
/// Copied with minor modifications from WebGPU standard.
///
/// Returns the HAL copy extent and the layer count.
///
/// [vtcr]: https://gpuweb.github.io/gpuweb/#validating-texture-copy-range
pub(crate) fn validate_texture_copy_range<T>(
    texture_copy_view: &wgt::TexelCopyTextureInfo<T>,
    desc: &wgt::TextureDescriptor<(), Vec<wgt::TextureFormat>>,
    texture_side: CopySide,
    copy_size: &Extent3d,
) -> Result<(hal::CopyExtent, u32), TransferError> {
    let (block_width, block_height) = desc.format.block_dimensions();

    let extent_virtual = desc.mip_level_size(texture_copy_view.mip_level).ok_or(
        TransferError::InvalidTextureMipLevel {
            level: texture_copy_view.mip_level,
            total: desc.mip_level_count,
        },
    )?;
    // physical size can be larger than the virtual
    let extent = extent_virtual.physical_size(desc.format);

    /// Return `Ok` if a run `size` texels long starting at `start_offset` falls
    /// entirely within `texture_size`. Otherwise, return an appropriate a`Err`.
    fn check_dimension(
        dimension: TextureErrorDimension,
        side: CopySide,
        start_offset: u32,
        size: u32,
        texture_size: u32,
    ) -> Result<(), TransferError> {
        // Avoid underflow in the subtraction by checking start_offset against
        // texture_size first.
        if start_offset <= texture_size && size <= texture_size - start_offset {
            Ok(())
        } else {
            Err(TransferError::TextureOverrun {
                start_offset,
                end_offset: start_offset.wrapping_add(size),
                texture_size,
                dimension,
                side,
            })
        }
    }

    check_dimension(
        TextureErrorDimension::X,
        texture_side,
        texture_copy_view.origin.x,
        copy_size.width,
        extent.width,
    )?;
    check_dimension(
        TextureErrorDimension::Y,
        texture_side,
        texture_copy_view.origin.y,
        copy_size.height,
        extent.height,
    )?;
    check_dimension(
        TextureErrorDimension::Z,
        texture_side,
        texture_copy_view.origin.z,
        copy_size.depth_or_array_layers,
        extent.depth_or_array_layers,
    )?;

    if texture_copy_view.origin.x % block_width != 0 {
        return Err(TransferError::UnalignedCopyOriginX);
    }
    if texture_copy_view.origin.y % block_height != 0 {
        return Err(TransferError::UnalignedCopyOriginY);
    }
    if copy_size.width % block_width != 0 {
        return Err(TransferError::UnalignedCopyWidth);
    }
    if copy_size.height % block_height != 0 {
        return Err(TransferError::UnalignedCopyHeight);
    }

    let (depth, array_layer_count) = match desc.dimension {
        wgt::TextureDimension::D1 => (1, 1),
        wgt::TextureDimension::D2 => (1, copy_size.depth_or_array_layers),
        wgt::TextureDimension::D3 => (copy_size.depth_or_array_layers, 1),
    };

    let copy_extent = hal::CopyExtent {
        width: copy_size.width,
        height: copy_size.height,
        depth,
    };
    Ok((copy_extent, array_layer_count))
}

fn handle_texture_init(
    init_kind: MemoryInitKind,
    cmd_buf_data: &mut CommandBufferMutable,
    device: &Device,
    copy_texture: &TexelCopyTextureInfo,
    copy_size: &Extent3d,
    texture: &Arc<Texture>,
    snatch_guard: &SnatchGuard<'_>,
) -> Result<(), ClearError> {
    let init_action = TextureInitTrackerAction {
        texture: texture.clone(),
        range: TextureInitRange {
            mip_range: copy_texture.mip_level..copy_texture.mip_level + 1,
            layer_range: copy_texture.origin.z
                ..(copy_texture.origin.z + copy_size.depth_or_array_layers),
        },
        kind: init_kind,
    };

    // Register the init action.
    let immediate_inits = cmd_buf_data
        .texture_memory_actions
        .register_init_action(&{ init_action });

    // In rare cases we may need to insert an init operation immediately onto the command buffer.
    if !immediate_inits.is_empty() {
        let cmd_buf_raw = cmd_buf_data.encoder.open()?;
        for init in immediate_inits {
            clear_texture(
                &init.texture,
                TextureInitRange {
                    mip_range: init.mip_level..(init.mip_level + 1),
                    layer_range: init.layer..(init.layer + 1),
                },
                cmd_buf_raw,
                &mut cmd_buf_data.trackers.textures,
                &device.alignments,
                device.zero_buffer.as_ref(),
                snatch_guard,
            )?;
        }
    }

    Ok(())
}

/// Prepare a transfer's source texture.
///
/// Ensure the source texture of a transfer is in the right initialization
/// state, and record the state for after the transfer operation.
fn handle_src_texture_init(
    cmd_buf_data: &mut CommandBufferMutable,
    device: &Device,
    source: &TexelCopyTextureInfo,
    copy_size: &Extent3d,
    texture: &Arc<Texture>,
    snatch_guard: &SnatchGuard<'_>,
) -> Result<(), TransferError> {
    handle_texture_init(
        MemoryInitKind::NeedsInitializedMemory,
        cmd_buf_data,
        device,
        source,
        copy_size,
        texture,
        snatch_guard,
    )?;
    Ok(())
}

/// Prepare a transfer's destination texture.
///
/// Ensure the destination texture of a transfer is in the right initialization
/// state, and record the state for after the transfer operation.
fn handle_dst_texture_init(
    cmd_buf_data: &mut CommandBufferMutable,
    device: &Device,
    destination: &TexelCopyTextureInfo,
    copy_size: &Extent3d,
    texture: &Arc<Texture>,
    snatch_guard: &SnatchGuard<'_>,
) -> Result<(), TransferError> {
    // Attention: If we don't write full texture subresources, we need to a full
    // clear first since we don't track subrects. This means that in rare cases
    // even a *destination* texture of a transfer may need an immediate texture
    // init.
    let dst_init_kind = if has_copy_partial_init_tracker_coverage(
        copy_size,
        destination.mip_level,
        &texture.desc,
    ) {
        MemoryInitKind::NeedsInitializedMemory
    } else {
        MemoryInitKind::ImplicitlyInitialized
    };

    handle_texture_init(
        dst_init_kind,
        cmd_buf_data,
        device,
        destination,
        copy_size,
        texture,
        snatch_guard,
    )?;
    Ok(())
}

impl Global {
    pub fn command_encoder_copy_buffer_to_buffer(
        &self,
        command_encoder_id: CommandEncoderId,
        source: BufferId,
        source_offset: BufferAddress,
        destination: BufferId,
        destination_offset: BufferAddress,
        size: BufferAddress,
    ) -> Result<(), CopyError> {
        profiling::scope!("CommandEncoder::copy_buffer_to_buffer");
        api_log!(
            "CommandEncoder::copy_buffer_to_buffer {source:?} -> {destination:?} {size:?}bytes"
        );

        if source == destination {
            return Err(TransferError::SameSourceDestinationBuffer.into());
        }
        let hub = &self.hub;

        let cmd_buf = hub
            .command_buffers
            .get(command_encoder_id.into_command_buffer_id());
        let mut cmd_buf_data = cmd_buf.data.lock();
        let mut cmd_buf_data_guard = cmd_buf_data.record()?;
        let cmd_buf_data = &mut *cmd_buf_data_guard;

        let device = &cmd_buf.device;
        device.check_is_valid()?;

        #[cfg(feature = "trace")]
        if let Some(ref mut list) = cmd_buf_data.commands {
            list.push(TraceCommand::CopyBufferToBuffer {
                src: source,
                src_offset: source_offset,
                dst: destination,
                dst_offset: destination_offset,
                size,
            });
        }

        let snatch_guard = device.snatchable_lock.read();

        let src_buffer = hub.buffers.get(source).get()?;

        src_buffer.same_device_as(cmd_buf.as_ref())?;

        let src_pending = cmd_buf_data
            .trackers
            .buffers
            .set_single(&src_buffer, hal::BufferUses::COPY_SRC);

        let src_raw = src_buffer.try_raw(&snatch_guard)?;
        src_buffer
            .check_usage(BufferUsages::COPY_SRC)
            .map_err(TransferError::MissingBufferUsage)?;
        // expecting only a single barrier
        let src_barrier = src_pending.map(|pending| pending.into_hal(&src_buffer, &snatch_guard));

        let dst_buffer = hub.buffers.get(destination).get()?;

        dst_buffer.same_device_as(cmd_buf.as_ref())?;

        let dst_pending = cmd_buf_data
            .trackers
            .buffers
            .set_single(&dst_buffer, hal::BufferUses::COPY_DST);

        let dst_raw = dst_buffer.try_raw(&snatch_guard)?;
        dst_buffer
            .check_usage(BufferUsages::COPY_DST)
            .map_err(TransferError::MissingBufferUsage)?;
        let dst_barrier = dst_pending.map(|pending| pending.into_hal(&dst_buffer, &snatch_guard));

        if size % wgt::COPY_BUFFER_ALIGNMENT != 0 {
            return Err(TransferError::UnalignedCopySize(size).into());
        }
        if source_offset % wgt::COPY_BUFFER_ALIGNMENT != 0 {
            return Err(TransferError::UnalignedBufferOffset(source_offset).into());
        }
        if destination_offset % wgt::COPY_BUFFER_ALIGNMENT != 0 {
            return Err(TransferError::UnalignedBufferOffset(destination_offset).into());
        }
        if !device
            .downlevel
            .flags
            .contains(wgt::DownlevelFlags::UNRESTRICTED_INDEX_BUFFER)
            && (src_buffer.usage.contains(BufferUsages::INDEX)
                || dst_buffer.usage.contains(BufferUsages::INDEX))
        {
            let forbidden_usages = BufferUsages::VERTEX
                | BufferUsages::UNIFORM
                | BufferUsages::INDIRECT
                | BufferUsages::STORAGE;
            if src_buffer.usage.intersects(forbidden_usages)
                || dst_buffer.usage.intersects(forbidden_usages)
            {
                return Err(TransferError::MissingDownlevelFlags(MissingDownlevelFlags(
                    wgt::DownlevelFlags::UNRESTRICTED_INDEX_BUFFER,
                ))
                .into());
            }
        }

        let source_end_offset = source_offset + size;
        let destination_end_offset = destination_offset + size;
        if source_end_offset > src_buffer.size {
            return Err(TransferError::BufferOverrun {
                start_offset: source_offset,
                end_offset: source_end_offset,
                buffer_size: src_buffer.size,
                side: CopySide::Source,
            }
            .into());
        }
        if destination_end_offset > dst_buffer.size {
            return Err(TransferError::BufferOverrun {
                start_offset: destination_offset,
                end_offset: destination_end_offset,
                buffer_size: dst_buffer.size,
                side: CopySide::Destination,
            }
            .into());
        }

        if size == 0 {
            log::trace!("Ignoring copy_buffer_to_buffer of size 0");
            cmd_buf_data_guard.mark_successful();
            return Ok(());
        }

        // Make sure source is initialized memory and mark dest as initialized.
        cmd_buf_data.buffer_memory_init_actions.extend(
            dst_buffer.initialization_status.read().create_action(
                &dst_buffer,
                destination_offset..(destination_offset + size),
                MemoryInitKind::ImplicitlyInitialized,
            ),
        );
        cmd_buf_data.buffer_memory_init_actions.extend(
            src_buffer.initialization_status.read().create_action(
                &src_buffer,
                source_offset..(source_offset + size),
                MemoryInitKind::NeedsInitializedMemory,
            ),
        );

        let region = hal::BufferCopy {
            src_offset: source_offset,
            dst_offset: destination_offset,
            size: wgt::BufferSize::new(size).unwrap(),
        };
        let cmd_buf_raw = cmd_buf_data.encoder.open()?;
        let barriers = src_barrier
            .into_iter()
            .chain(dst_barrier)
            .collect::<Vec<_>>();
        unsafe {
            cmd_buf_raw.transition_buffers(&barriers);
            cmd_buf_raw.copy_buffer_to_buffer(src_raw, dst_raw, &[region]);
        }

        cmd_buf_data_guard.mark_successful();
        Ok(())
    }

    pub fn command_encoder_copy_buffer_to_texture(
        &self,
        command_encoder_id: CommandEncoderId,
        source: &TexelCopyBufferInfo,
        destination: &TexelCopyTextureInfo,
        copy_size: &Extent3d,
    ) -> Result<(), CopyError> {
        profiling::scope!("CommandEncoder::copy_buffer_to_texture");
        api_log!(
            "CommandEncoder::copy_buffer_to_texture {:?} -> {:?} {copy_size:?}",
            source.buffer,
            destination.texture
        );

        let hub = &self.hub;

        let cmd_buf = hub
            .command_buffers
            .get(command_encoder_id.into_command_buffer_id());
        let mut cmd_buf_data = cmd_buf.data.lock();
        let mut cmd_buf_data_guard = cmd_buf_data.record()?;
        let cmd_buf_data = &mut *cmd_buf_data_guard;

        let device = &cmd_buf.device;
        device.check_is_valid()?;

        #[cfg(feature = "trace")]
        if let Some(ref mut list) = cmd_buf_data.commands {
            list.push(TraceCommand::CopyBufferToTexture {
                src: *source,
                dst: *destination,
                size: *copy_size,
            });
        }

        if copy_size.width == 0 || copy_size.height == 0 || copy_size.depth_or_array_layers == 0 {
            log::trace!("Ignoring copy_buffer_to_texture of size 0");
            cmd_buf_data_guard.mark_successful();
            return Ok(());
        }

        let dst_texture = hub.textures.get(destination.texture).get()?;

        dst_texture.same_device_as(cmd_buf.as_ref())?;

        let (hal_copy_size, array_layer_count) = validate_texture_copy_range(
            destination,
            &dst_texture.desc,
            CopySide::Destination,
            copy_size,
        )?;

        let (dst_range, dst_base) = extract_texture_selector(destination, copy_size, &dst_texture)?;

        let snatch_guard = device.snatchable_lock.read();

        // Handle texture init *before* dealing with barrier transitions so we
        // have an easier time inserting "immediate-inits" that may be required
        // by prior discards in rare cases.
        handle_dst_texture_init(
            cmd_buf_data,
            device,
            destination,
            copy_size,
            &dst_texture,
            &snatch_guard,
        )?;

        let src_buffer = hub.buffers.get(source.buffer).get()?;

        src_buffer.same_device_as(cmd_buf.as_ref())?;

        let src_pending = cmd_buf_data
            .trackers
            .buffers
            .set_single(&src_buffer, hal::BufferUses::COPY_SRC);

        let src_raw = src_buffer.try_raw(&snatch_guard)?;
        src_buffer
            .check_usage(BufferUsages::COPY_SRC)
            .map_err(TransferError::MissingBufferUsage)?;
        let src_barrier = src_pending.map(|pending| pending.into_hal(&src_buffer, &snatch_guard));

        let dst_pending = cmd_buf_data.trackers.textures.set_single(
            &dst_texture,
            dst_range,
            hal::TextureUses::COPY_DST,
        );
        let dst_raw = dst_texture.try_raw(&snatch_guard)?;
        dst_texture
            .check_usage(TextureUsages::COPY_DST)
            .map_err(TransferError::MissingTextureUsage)?;
        let dst_barrier = dst_pending
            .map(|pending| pending.into_hal(dst_raw))
            .collect::<Vec<_>>();

        if !dst_base.aspect.is_one() {
            return Err(TransferError::CopyAspectNotOne.into());
        }

        if !conv::is_valid_copy_dst_texture_format(dst_texture.desc.format, destination.aspect) {
            return Err(TransferError::CopyToForbiddenTextureFormat {
                format: dst_texture.desc.format,
                aspect: destination.aspect,
            }
            .into());
        }

        let (required_buffer_bytes_in_copy, bytes_per_array_layer) = validate_linear_texture_data(
            &source.layout,
            dst_texture.desc.format,
            destination.aspect,
            src_buffer.size,
            CopySide::Source,
            copy_size,
            true,
        )?;

        if dst_texture.desc.format.is_depth_stencil_format() {
            device
                .require_downlevel_flags(wgt::DownlevelFlags::DEPTH_TEXTURE_AND_BUFFER_COPIES)
                .map_err(TransferError::from)?;
        }

        cmd_buf_data.buffer_memory_init_actions.extend(
            src_buffer.initialization_status.read().create_action(
                &src_buffer,
                source.layout.offset..(source.layout.offset + required_buffer_bytes_in_copy),
                MemoryInitKind::NeedsInitializedMemory,
            ),
        );

        let regions = (0..array_layer_count)
            .map(|rel_array_layer| {
                let mut texture_base = dst_base.clone();
                texture_base.array_layer += rel_array_layer;
                let mut buffer_layout = source.layout;
                buffer_layout.offset += rel_array_layer as u64 * bytes_per_array_layer;
                hal::BufferTextureCopy {
                    buffer_layout,
                    texture_base,
                    size: hal_copy_size,
                }
            })
            .collect::<Vec<_>>();

        let cmd_buf_raw = cmd_buf_data.encoder.open()?;
        unsafe {
            cmd_buf_raw.transition_textures(&dst_barrier);
            cmd_buf_raw.transition_buffers(src_barrier.as_slice());
            cmd_buf_raw.copy_buffer_to_texture(src_raw, dst_raw, &regions);
        }

        cmd_buf_data_guard.mark_successful();
        Ok(())
    }

    pub fn command_encoder_copy_texture_to_buffer(
        &self,
        command_encoder_id: CommandEncoderId,
        source: &TexelCopyTextureInfo,
        destination: &TexelCopyBufferInfo,
        copy_size: &Extent3d,
    ) -> Result<(), CopyError> {
        profiling::scope!("CommandEncoder::copy_texture_to_buffer");
        api_log!(
            "CommandEncoder::copy_texture_to_buffer {:?} -> {:?} {copy_size:?}",
            source.texture,
            destination.buffer
        );

        let hub = &self.hub;

        let cmd_buf = hub
            .command_buffers
            .get(command_encoder_id.into_command_buffer_id());
        let mut cmd_buf_data = cmd_buf.data.lock();
        let mut cmd_buf_data_guard = cmd_buf_data.record()?;
        let cmd_buf_data = &mut *cmd_buf_data_guard;

        let device = &cmd_buf.device;
        device.check_is_valid()?;

        #[cfg(feature = "trace")]
        if let Some(list) = cmd_buf_data.commands.as_mut() {
            list.push(TraceCommand::CopyTextureToBuffer {
                src: *source,
                dst: *destination,
                size: *copy_size,
            });
        }

        if copy_size.width == 0 || copy_size.height == 0 || copy_size.depth_or_array_layers == 0 {
            log::trace!("Ignoring copy_texture_to_buffer of size 0");
            cmd_buf_data_guard.mark_successful();
            return Ok(());
        }

        let src_texture = hub.textures.get(source.texture).get()?;

        src_texture.same_device_as(cmd_buf.as_ref())?;

        let (hal_copy_size, array_layer_count) =
            validate_texture_copy_range(source, &src_texture.desc, CopySide::Source, copy_size)?;

        let (src_range, src_base) = extract_texture_selector(source, copy_size, &src_texture)?;

        let snatch_guard = device.snatchable_lock.read();

        // Handle texture init *before* dealing with barrier transitions so we
        // have an easier time inserting "immediate-inits" that may be required
        // by prior discards in rare cases.
        handle_src_texture_init(
            cmd_buf_data,
            device,
            source,
            copy_size,
            &src_texture,
            &snatch_guard,
        )?;

        let src_pending = cmd_buf_data.trackers.textures.set_single(
            &src_texture,
            src_range,
            hal::TextureUses::COPY_SRC,
        );
        let src_raw = src_texture.try_raw(&snatch_guard)?;
        src_texture
            .check_usage(TextureUsages::COPY_SRC)
            .map_err(TransferError::MissingTextureUsage)?;
        if src_texture.desc.sample_count != 1 {
            return Err(TransferError::InvalidSampleCount {
                sample_count: src_texture.desc.sample_count,
            }
            .into());
        }
        if source.mip_level >= src_texture.desc.mip_level_count {
            return Err(TransferError::InvalidMipLevel {
                requested: source.mip_level,
                count: src_texture.desc.mip_level_count,
            }
            .into());
        }
        let src_barrier = src_pending
            .map(|pending| pending.into_hal(src_raw))
            .collect::<Vec<_>>();

        let dst_buffer = hub.buffers.get(destination.buffer).get()?;

        dst_buffer.same_device_as(cmd_buf.as_ref())?;

        let dst_pending = cmd_buf_data
            .trackers
            .buffers
            .set_single(&dst_buffer, hal::BufferUses::COPY_DST);

        let dst_raw = dst_buffer.try_raw(&snatch_guard)?;
        dst_buffer
            .check_usage(BufferUsages::COPY_DST)
            .map_err(TransferError::MissingBufferUsage)?;
        let dst_barrier = dst_pending.map(|pending| pending.into_hal(&dst_buffer, &snatch_guard));

        if !src_base.aspect.is_one() {
            return Err(TransferError::CopyAspectNotOne.into());
        }

        if !conv::is_valid_copy_src_texture_format(src_texture.desc.format, source.aspect) {
            return Err(TransferError::CopyFromForbiddenTextureFormat {
                format: src_texture.desc.format,
                aspect: source.aspect,
            }
            .into());
        }

        let (required_buffer_bytes_in_copy, bytes_per_array_layer) = validate_linear_texture_data(
            &destination.layout,
            src_texture.desc.format,
            source.aspect,
            dst_buffer.size,
            CopySide::Destination,
            copy_size,
            true,
        )?;

        if src_texture.desc.format.is_depth_stencil_format() {
            device
                .require_downlevel_flags(wgt::DownlevelFlags::DEPTH_TEXTURE_AND_BUFFER_COPIES)
                .map_err(TransferError::from)?;
        }

        cmd_buf_data.buffer_memory_init_actions.extend(
            dst_buffer.initialization_status.read().create_action(
                &dst_buffer,
                destination.layout.offset
                    ..(destination.layout.offset + required_buffer_bytes_in_copy),
                MemoryInitKind::ImplicitlyInitialized,
            ),
        );

        let regions = (0..array_layer_count)
            .map(|rel_array_layer| {
                let mut texture_base = src_base.clone();
                texture_base.array_layer += rel_array_layer;
                let mut buffer_layout = destination.layout;
                buffer_layout.offset += rel_array_layer as u64 * bytes_per_array_layer;
                hal::BufferTextureCopy {
                    buffer_layout,
                    texture_base,
                    size: hal_copy_size,
                }
            })
            .collect::<Vec<_>>();
        let cmd_buf_raw = cmd_buf_data.encoder.open()?;
        unsafe {
            cmd_buf_raw.transition_buffers(dst_barrier.as_slice());
            cmd_buf_raw.transition_textures(&src_barrier);
            cmd_buf_raw.copy_texture_to_buffer(
                src_raw,
                hal::TextureUses::COPY_SRC,
                dst_raw,
                &regions,
            );
        }

        cmd_buf_data_guard.mark_successful();
        Ok(())
    }

    pub fn command_encoder_copy_texture_to_texture(
        &self,
        command_encoder_id: CommandEncoderId,
        source: &TexelCopyTextureInfo,
        destination: &TexelCopyTextureInfo,
        copy_size: &Extent3d,
    ) -> Result<(), CopyError> {
        profiling::scope!("CommandEncoder::copy_texture_to_texture");
        api_log!(
            "CommandEncoder::copy_texture_to_texture {:?} -> {:?} {copy_size:?}",
            source.texture,
            destination.texture
        );

        let hub = &self.hub;

        let cmd_buf = hub
            .command_buffers
            .get(command_encoder_id.into_command_buffer_id());
        let mut cmd_buf_data = cmd_buf.data.lock();
        let mut cmd_buf_data_guard = cmd_buf_data.record()?;
        let cmd_buf_data = &mut *cmd_buf_data_guard;

        let device = &cmd_buf.device;
        device.check_is_valid()?;

        let snatch_guard = device.snatchable_lock.read();

        #[cfg(feature = "trace")]
        if let Some(ref mut list) = cmd_buf_data.commands {
            list.push(TraceCommand::CopyTextureToTexture {
                src: *source,
                dst: *destination,
                size: *copy_size,
            });
        }

        if copy_size.width == 0 || copy_size.height == 0 || copy_size.depth_or_array_layers == 0 {
            log::trace!("Ignoring copy_texture_to_texture of size 0");
            cmd_buf_data_guard.mark_successful();
            return Ok(());
        }

        let src_texture = hub.textures.get(source.texture).get()?;
        let dst_texture = hub.textures.get(destination.texture).get()?;

        src_texture.same_device_as(cmd_buf.as_ref())?;
        dst_texture.same_device_as(cmd_buf.as_ref())?;

        // src and dst texture format must be copy-compatible
        // https://gpuweb.github.io/gpuweb/#copy-compatible
        if src_texture.desc.format.remove_srgb_suffix()
            != dst_texture.desc.format.remove_srgb_suffix()
        {
            return Err(TransferError::TextureFormatsNotCopyCompatible {
                src_format: src_texture.desc.format,
                dst_format: dst_texture.desc.format,
            }
            .into());
        }

        let (src_copy_size, array_layer_count) =
            validate_texture_copy_range(source, &src_texture.desc, CopySide::Source, copy_size)?;
        let (dst_copy_size, _) = validate_texture_copy_range(
            destination,
            &dst_texture.desc,
            CopySide::Destination,
            copy_size,
        )?;

        let (src_range, src_tex_base) = extract_texture_selector(source, copy_size, &src_texture)?;
        let (dst_range, dst_tex_base) =
            extract_texture_selector(destination, copy_size, &dst_texture)?;
        let src_texture_aspects = hal::FormatAspects::from(src_texture.desc.format);
        let dst_texture_aspects = hal::FormatAspects::from(dst_texture.desc.format);
        if src_tex_base.aspect != src_texture_aspects {
            return Err(TransferError::CopySrcMissingAspects.into());
        }
        if dst_tex_base.aspect != dst_texture_aspects {
            return Err(TransferError::CopyDstMissingAspects.into());
        }

        // Handle texture init *before* dealing with barrier transitions so we
        // have an easier time inserting "immediate-inits" that may be required
        // by prior discards in rare cases.
        handle_src_texture_init(
            cmd_buf_data,
            device,
            source,
            copy_size,
            &src_texture,
            &snatch_guard,
        )?;
        handle_dst_texture_init(
            cmd_buf_data,
            device,
            destination,
            copy_size,
            &dst_texture,
            &snatch_guard,
        )?;

        let src_pending = cmd_buf_data.trackers.textures.set_single(
            &src_texture,
            src_range,
            hal::TextureUses::COPY_SRC,
        );
        let src_raw = src_texture.try_raw(&snatch_guard)?;
        src_texture
            .check_usage(TextureUsages::COPY_SRC)
            .map_err(TransferError::MissingTextureUsage)?;

        //TODO: try to avoid this the collection. It's needed because both
        // `src_pending` and `dst_pending` try to hold `trackers.textures` mutably.
        let mut barriers: ArrayVec<_, 2> = src_pending
            .map(|pending| pending.into_hal(src_raw))
            .collect();

        let dst_pending = cmd_buf_data.trackers.textures.set_single(
            &dst_texture,
            dst_range,
            hal::TextureUses::COPY_DST,
        );
        let dst_raw = dst_texture.try_raw(&snatch_guard)?;
        dst_texture
            .check_usage(TextureUsages::COPY_DST)
            .map_err(TransferError::MissingTextureUsage)?;

        barriers.extend(dst_pending.map(|pending| pending.into_hal(dst_raw)));

        let hal_copy_size = hal::CopyExtent {
            width: src_copy_size.width.min(dst_copy_size.width),
            height: src_copy_size.height.min(dst_copy_size.height),
            depth: src_copy_size.depth.min(dst_copy_size.depth),
        };
        let regions = (0..array_layer_count)
            .map(|rel_array_layer| {
                let mut src_base = src_tex_base.clone();
                let mut dst_base = dst_tex_base.clone();
                src_base.array_layer += rel_array_layer;
                dst_base.array_layer += rel_array_layer;
                hal::TextureCopy {
                    src_base,
                    dst_base,
                    size: hal_copy_size,
                }
            })
            .collect::<Vec<_>>();
        let cmd_buf_raw = cmd_buf_data.encoder.open()?;
        unsafe {
            cmd_buf_raw.transition_textures(&barriers);
            cmd_buf_raw.copy_texture_to_texture(
                src_raw,
                hal::TextureUses::COPY_SRC,
                dst_raw,
                &regions,
            );
        }

        cmd_buf_data_guard.mark_successful();
        Ok(())
    }
}