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