On Tue, Nov 29, 2022 at 09:15:24PM +0000, hinxx wrote: > I'm looking to use a sendfile(2) with a Xilinx XDMA kernel driver in order to move data from a PCIe board with Xilinx FPGA to the network card with "zero-copy". > > Currently I'm getting EINVAL return status from sendfile(2) when providing opened XDMA device file descriptor as input fd. > > The device driver provides a character device that can be mmap'ed. > > There seem to be other restrictions. Can anyone provide insight on what would be needed to make this work? Please contact the authors of your kernel driver, they can answer this best. good luck! greg k-h