Process memory DMA access from devices, kiobuf ?

[Terry Barnaby <terry@beam.demon.co.uk>]

Hi,

We are doing work with FPGA's and have a Linux driver for a particular
board that has these
devices. For performance reasons the driver has the ability to DMA
directly to process (user)
memory. We have made use of the kiobuf routines such as
"map_user_kiobuf()" to map into
physical memory the user address space.
I note that the RedHat kernels have a patched kernel containing the
kiobuf code but the
standard linux source does not right up to 2.4.2.
Is there a better recommended way to perform DMA access to user memory
from a device
using the Linux kernel ?

Cheers

Terry

--
  Dr Terry Barnaby                     BEAM Ltd
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