On 11/01/17 09:54 PM, Stephen Bates wrote:
The iopmem patchset addressed all the use cases above and while it is
an in kernel API it could have been modified to be one reasonably easily.
As Logan states the driver can then choose to pass the VMAs to user-space
in a manner that makes sense.
Just to clarify: the iopmem patchset had one patch that allowed for
slightly more flexible zone device mappings which ought to be useful for
The other patch (which was iopmem proper) was more of an example of how
the zone_device memory _could_ be exposed to userspace with "iopmem"
hardware that looks similar to nvdimm hardware. Iopmem was not really
useful, in itself, for NVMe devices and it was never expected to be
useful for GPUs.