Re: [PATCH v5 28/28] fpga: dfl: afu: add DFL_FPGA_PORT_DMA_MAP/UNMAP ioctls support

Alan Tull
2018-06-06T16:09:23Z

On Tue, May 1, 2018 at 9:50 PM, Wu Hao <hao.wu@intel.com> wrote:

Hi Hao,

> DMA memory regions are required for Accelerated Function Unit (AFU) usage.
> These two ioctls allow user space applications to map user memory regions
> for dma, and unmap them after use. Iova is returned from driver to user
> space application via DFL_FPGA_PORT_DMA_MAP ioctl. Application needs to unmap
> it after use, otherwise, driver will unmap them in device file release
> operation.
>
> Each AFU has its own rb tree to keep track of its mapped DMA regions.
>
> Ioctl interfaces:
> * DFL_FPGA_PORT_DMA_MAP
> Do the dma mapping per user_addr and length which provided by user.
> Return iova in provided struct dfl_fpga_port_dma_map.
>
> * DFL_FPGA_PORT_DMA_UNMAP
> Unmap the dma region per iova provided by user.
>
> Signed-off-by: Tim Whisonant <tim.whisonant@intel.com>
> Signed-off-by: Enno Luebbers <enno.luebbers@intel.com>
> Signed-off-by: Shiva Rao <shiva.rao@intel.com>
> Signed-off-by: Christopher Rauer <christopher.rauer@intel.com>
> Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
> Signed-off-by: Wu Hao <hao.wu@intel.com>

Acked-by: Alan Tull <atull@kernel.org>