Merge tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma

Pull hmm updates from Jason Gunthorpe:
 "Ralph has been working on nouveau's use of hmm_range_fault() and
  migrate_vma() which resulted in this small series. It adds reporting
  of the page table order from hmm_range_fault() and some optimization
  of migrate_vma():

   - Report the size of the page table mapping out of hmm_range_fault().

     This makes it easier to establish a large/huge/etc mapping in the
     device's page table.

   - Allow devices to ignore the invalidations during migration in cases
     where the migration is not going to change pages.

     For instance migrating pages to a device does not require the
     device to invalidate pages already in the device.

   - Update nouveau and hmm_tests to use the above"

* tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
  mm/hmm/test: use the new migration invalidation
  nouveau/svm: use the new migration invalidation
  mm/notifier: add migration invalidation type
  mm/migrate: add a flags parameter to migrate_vma
  nouveau: fix storing invalid ptes
  nouveau/hmm: support mapping large sysmem pages
  nouveau: fix mapping 2MB sysmem pages
  nouveau/hmm: fault one page at a time
  mm/hmm: add tests for hmm_pfn_to_map_order()
  mm/hmm: provide the page mapping order in hmm_range_fault()

1 files changed, 11 insertions, 3 deletions

diff --git a/mm/migrate.c b/mm/migrate.c
index 40cd7016ae6f..4fcc465736ff 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -2276,7 +2276,9 @@ again:
 				goto next;
 
 			page = device_private_entry_to_page(entry);
-			if (page->pgmap->owner != migrate->src_owner)
+			if (!(migrate->flags &
+				MIGRATE_VMA_SELECT_DEVICE_PRIVATE) ||
+			    page->pgmap->owner != migrate->pgmap_owner)
 				goto next;
 
 			mpfn = migrate_pfn(page_to_pfn(page)) |
@@ -2284,7 +2286,7 @@ again:
 			if (is_write_device_private_entry(entry))
 				mpfn |= MIGRATE_PFN_WRITE;
 		} else {
-			if (migrate->src_owner)
+			if (!(migrate->flags & MIGRATE_VMA_SELECT_SYSTEM))
 				goto next;
 			pfn = pte_pfn(pte);
 			if (is_zero_pfn(pfn)) {
@@ -2379,8 +2381,14 @@ static void migrate_vma_collect(struct migrate_vma *migrate)
 {
 	struct mmu_notifier_range range;
 
-	mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, NULL,
+	/*
+	 * Note that the pgmap_owner is passed to the mmu notifier callback so
+	 * that the registered device driver can skip invalidating device
+	 * private page mappings that won't be migrated.
+	 */
+	mmu_notifier_range_init(&range, MMU_NOTIFY_MIGRATE, 0, migrate->vma,
 			migrate->vma->vm_mm, migrate->start, migrate->end);
+	range.migrate_pgmap_owner = migrate->pgmap_owner;
 	mmu_notifier_invalidate_range_start(&range);
 
 	walk_page_range(migrate->vma->vm_mm, migrate->start, migrate->end,