On Wed, Jul 01, 2020 at 03:53:47PM -0700, Ralph Campbell wrote: > The goal for this series is to introduce the hmm_pfn_to_map_order() > function. This allows a device driver to know that a given 4K PFN is > actually mapped by the CPU using a larger sized CPU page table entry and > therefore the device driver can safely map system memory using larger > device MMU PTEs. > The series is based on 5.8.0-rc3 and is intended for Jason Gunthorpe's > hmm tree. These were originally part of a larger series: > https://lore.kernel.org/linux-mm/20200619215649.32297-1-rcampbell@xxxxxxxxxx/ > > Changes in v3: > Replaced the HMM_PFN_P[MU]D flags with hmm_pfn_to_map_order() to > indicate the size of the CPU mapping. > > Changes in v2: > Make the hmm_range_fault() API changes into a separate series and add > two output flags for PMD/PUD instead of a single compund page flag as > suggested by Jason Gunthorpe. > Make the nouveau page table changes a separate patch as suggested by > Ben Skeggs. > Only add support for 2MB nouveau mappings initially since changing the > 1:1 CPU/GPU page table size assumptions requires a bigger set of changes. > Rebase to 5.8.0-rc3. > > Ralph Campbell (5): > nouveau/hmm: fault one page at a time > mm/hmm: add hmm_mapping order > nouveau: fix mapping 2MB sysmem pages > nouveau/hmm: support mapping large sysmem pages > hmm: add tests for HMM_PFN_PMD flag Applied to hmm.git. I edited the comment for hmm_pfn_to_map_order() and added a function to compute the field. Thanks, Jason