Host methods exist to do at least some of what we need, but we are not
currently pushing replay/cancels through a channel like UVM does as it's
not clear whether it's necessary in our case (UVM also updates PTEs with
the GPU).
UVM also pushes a software method for fault cancels on Pascal, seemingly
because the host methods don't appear to be sufficient. If/when we want
to push the replay/cancel on the GPU, we can re-purpose the cancellation
code here to implement that swmthd.
Keep it simple for now, until we figure out exactly what we need here.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
This provides a somewhat more direct method of manipulating the GPU page
tables, which will be required to support SVM.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
NVKM is currently responsible for managing the allocation of a client's
GPU address-space, but there's various use-cases (ie. HMM address-space
mirroring) where giving a client more direct control is desirable.
This commit allows for a VMM to be created where the area allocated for
NVKM is limited to a client-specified window, the remainder of address-
space is controlled directly by the client.
Leaving a window is necessary to support various internal requirements,
but also to support existing allocation interfaces as not all of the HW
is capable of working with a HMM allocation.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
This is the first chunk of the new VMM code that provides the structures
needed to describe a GPU virtual address-space layout, as well as common
interfaces to handle VMM creation, and connecting instances to a VMM.
The constructor now allocates the PD itself, rather than having the user
handle that manually. This won't/can't be used until after all backends
have been ported to these interfaces, so a little bit of memory will be
wasted on Fermi and newer for a couple of commits in the series.
Compatibility has been hacked into the old code to allow each GPU backend
to be ported individually.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
