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73 lines
1.7 KiB
73 lines
1.7 KiB
Buffer Sharing and Synchronization
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==================================
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The dma-buf subsystem provides the framework for sharing buffers for
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hardware (DMA) access across multiple device drivers and subsystems, and
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for synchronizing asynchronous hardware access.
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This is used, for example, by drm "prime" multi-GPU support, but is of
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course not limited to GPU use cases.
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The three main components of this are: (1) dma-buf, representing a
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sg_table and exposed to userspace as a file descriptor to allow passing
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between devices, (2) fence, which provides a mechanism to signal when
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one device as finished access, and (3) reservation, which manages the
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shared or exclusive fence(s) associated with the buffer.
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Shared DMA Buffers
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------------------
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.. kernel-doc:: drivers/dma-buf/dma-buf.c
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:export:
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.. kernel-doc:: include/linux/dma-buf.h
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:internal:
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Reservation Objects
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-------------------
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.. kernel-doc:: drivers/dma-buf/reservation.c
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:doc: Reservation Object Overview
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.. kernel-doc:: drivers/dma-buf/reservation.c
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:export:
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.. kernel-doc:: include/linux/reservation.h
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:internal:
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DMA Fences
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----------
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.. kernel-doc:: drivers/dma-buf/dma-fence.c
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:export:
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.. kernel-doc:: include/linux/dma-fence.h
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:internal:
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Seqno Hardware Fences
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~~~~~~~~~~~~~~~~~~~~~
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.. kernel-doc:: drivers/dma-buf/seqno-fence.c
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:export:
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.. kernel-doc:: include/linux/seqno-fence.h
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:internal:
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DMA Fence Array
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~~~~~~~~~~~~~~~
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.. kernel-doc:: drivers/dma-buf/dma-fence-array.c
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:export:
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.. kernel-doc:: include/linux/dma-fence-array.h
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:internal:
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DMA Fence uABI/Sync File
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~~~~~~~~~~~~~~~~~~~~~~~~
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.. kernel-doc:: drivers/dma-buf/sync_file.c
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:export:
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.. kernel-doc:: include/linux/sync_file.h
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:internal:
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