6 Apr
2018
6 Apr
'18
9:52 a.m.
Hi Gerd,
On 14 March 2018 at 08:03, Gerd Hoffmann kraxel@redhat.com wrote:
Either mlock account (because it's mlocked defacto), and get_user_pages won't do that for you.
Or you write the full-blown userptr implementation, including mmu_notifier support (see i915 or amdgpu), but that also requires Christian Königs latest ->invalidate_mapping RFC for dma-buf (since atm exporting userptr buffers is a no-go).
I guess I'll look at mlock accounting for starters then. Easier for now, and leaves the door open to switch to userptr later as this should be transparent to userspace.
Out of interest, do you have usecases for full userptr support? Maybe another way would be to allow creation of dmabufs from memfds.
Cheers, Daniel