mirror of https://gitee.com/openkylin/linux.git
dma-buf: Cleanup comments on dma_buf_map_attachment()
Mappings need to be unmapped by calling dma_buf_unmap_attachment() and not by calling again dma_buf_map_attachment(). Also fix some spelling mistakes. Signed-off-by: Liviu Dudau <liviu.dudau@arm.com> Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Reviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.com> Link: https://patchwork.freedesktop.org/patch/msgid/20171101140630.2884-1-Liviu.Dudau@arm.com
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@ -351,13 +351,13 @@ static inline int is_dma_buf_file(struct file *file)
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*
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* 2. Userspace passes this file-descriptors to all drivers it wants this buffer
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* to share with: First the filedescriptor is converted to a &dma_buf using
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* dma_buf_get(). The the buffer is attached to the device using
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* dma_buf_get(). Then the buffer is attached to the device using
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* dma_buf_attach().
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*
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* Up to this stage the exporter is still free to migrate or reallocate the
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* backing storage.
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*
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* 3. Once the buffer is attached to all devices userspace can inniate DMA
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* 3. Once the buffer is attached to all devices userspace can initiate DMA
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* access to the shared buffer. In the kernel this is done by calling
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* dma_buf_map_attachment() and dma_buf_unmap_attachment().
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*
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@ -617,7 +617,7 @@ EXPORT_SYMBOL_GPL(dma_buf_detach);
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* Returns sg_table containing the scatterlist to be returned; returns ERR_PTR
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* on error. May return -EINTR if it is interrupted by a signal.
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*
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* A mapping must be unmapped again using dma_buf_map_attachment(). Note that
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* A mapping must be unmapped by using dma_buf_unmap_attachment(). Note that
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* the underlying backing storage is pinned for as long as a mapping exists,
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* therefore users/importers should not hold onto a mapping for undue amounts of
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* time.
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