> From: Jason Gunthorpe <jgg@xxxxxxxxxx> > Sent: Thursday, October 10, 2024 12:23 AM > > HW with CANWBS is always cache coherent and ignores PCI No Snoop > requests > as well. This meets the requirement for > IOMMU_CAP_ENFORCE_CACHE_COHERENCY, > so let's return it. > > Implement the enforce_cache_coherency() op to reject attaching devices > that don't have CANWBS. > > Reviewed-by: Nicolin Chen <nicolinc@xxxxxxxxxx> > Reviewed-by: Mostafa Saleh <smostafa@xxxxxxxxxx> > Tested-by: Nicolin Chen <nicolinc@xxxxxxxxxx> > Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx> Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx>