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

Pull hmm updates from Jason Gunthorpe:
 "This is more cleanup and consolidation of the hmm APIs and the very
  strongly related mmu_notifier interfaces. Many places across the tree
  using these interfaces are touched in the process. Beyond that a
  cleanup to the page walker API and a few memremap related changes
  round out the series:

   - General improvement of hmm_range_fault() and related APIs, more
     documentation, bug fixes from testing, API simplification &
     consolidation, and unused API removal

   - Simplify the hmm related kconfigs to HMM_MIRROR and DEVICE_PRIVATE,
     and make them internal kconfig selects

   - Hoist a lot of code related to mmu notifier attachment out of
     drivers by using a refcount get/put attachment idiom and remove the
     convoluted mmu_notifier_unregister_no_release() and related APIs.

   - General API improvement for the migrate_vma API and revision of its
     only user in nouveau

   - Annotate mmu_notifiers with lockdep and sleeping region debugging

  Two series unrelated to HMM or mmu_notifiers came along due to
  dependencies:

   - Allow pagemap's memremap_pages family of APIs to work without
     providing a struct device

   - Make walk_page_range() and related use a constant structure for
     function pointers"

* tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (75 commits)
  libnvdimm: Enable unit test infrastructure compile checks
  mm, notifier: Catch sleeping/blocking for !blockable
  kernel.h: Add non_block_start/end()
  drm/radeon: guard against calling an unpaired radeon_mn_unregister()
  csky: add missing brackets in a macro for tlb.h
  pagewalk: use lockdep_assert_held for locking validation
  pagewalk: separate function pointers from iterator data
  mm: split out a new pagewalk.h header from mm.h
  mm/mmu_notifiers: annotate with might_sleep()
  mm/mmu_notifiers: prime lockdep
  mm/mmu_notifiers: add a lockdep map for invalidate_range_start/end
  mm/mmu_notifiers: remove the __mmu_notifier_invalidate_range_start/end exports
  mm/hmm: hmm_range_fault() infinite loop
  mm/hmm: hmm_range_fault() NULL pointer bug
  mm/hmm: fix hmm_range_fault()'s handling of swapped out pages
  mm/mmu_notifiers: remove unregister_no_release
  RDMA/odp: remove ib_ucontext from ib_umem
  RDMA/odp: use mmu_notifier_get/put for 'struct ib_ucontext_per_mm'
  RDMA/mlx5: Use odp instead of mr->umem in pagefault_mr
  RDMA/mlx5: Use ib_umem_start instead of umem.address
  ...

drivers/infiniband/hw/mlx5/mr.c

@@ -784,19 +784,37 @@ static int mr_umem_get(struct mlx5_ib_dev *dev, struct ib_udata *udata,
 		       int *ncont, int *order)
 {
 	struct ib_umem *u;
-	int err;
 
 	*umem = NULL;
 
-	u = ib_umem_get(udata, start, length, access_flags, 0);
-	err = PTR_ERR_OR_ZERO(u);
-	if (err) {
-		mlx5_ib_dbg(dev, "umem get failed (%d)\n", err);
-		return err;
+	if (access_flags & IB_ACCESS_ON_DEMAND) {
+		struct ib_umem_odp *odp;
+
+		odp = ib_umem_odp_get(udata, start, length, access_flags);
+		if (IS_ERR(odp)) {
+			mlx5_ib_dbg(dev, "umem get failed (%ld)\n",
+				    PTR_ERR(odp));
+			return PTR_ERR(odp);
+		}
+
+		u = &odp->umem;
+
+		*page_shift = odp->page_shift;
+		*ncont = ib_umem_odp_num_pages(odp);
+		*npages = *ncont << (*page_shift - PAGE_SHIFT);
+		if (order)
+			*order = ilog2(roundup_pow_of_two(*ncont));
+	} else {
+		u = ib_umem_get(udata, start, length, access_flags, 0);
+		if (IS_ERR(u)) {
+			mlx5_ib_dbg(dev, "umem get failed (%ld)\n", PTR_ERR(u));
+			return PTR_ERR(u);
+		}
+
+		mlx5_ib_cont_pages(u, start, MLX5_MKEY_PAGE_SHIFT_MASK, npages,
+				   page_shift, ncont, order);
 	}
 
-	mlx5_ib_cont_pages(u, start, MLX5_MKEY_PAGE_SHIFT_MASK, npages,
-			   page_shift, ncont, order);
 	if (!*npages) {
 		mlx5_ib_warn(dev, "avoid zero region\n");
 		ib_umem_release(u);
@@ -1599,7 +1617,7 @@ static void dereg_mr(struct mlx5_ib_dev *dev, struct mlx5_ib_mr *mr)
 		/* Wait for all running page-fault handlers to finish. */
 		synchronize_srcu(&dev->mr_srcu);
 		/* Destroy all page mappings */
-		if (umem_odp->page_list)
+		if (!umem_odp->is_implicit_odp)
 			mlx5_ib_invalidate_range(umem_odp,
 						 ib_umem_start(umem_odp),
 						 ib_umem_end(umem_odp));
@@ -1610,7 +1628,7 @@ static void dereg_mr(struct mlx5_ib_dev *dev, struct mlx5_ib_mr *mr)
 		 * so that there will not be any invalidations in
 		 * flight, looking at the *mr struct.
 		 */
-		ib_umem_release(umem);
+		ib_umem_odp_release(umem_odp);
 		atomic_sub(npages, &dev->mdev->priv.reg_pages);
 
 		/* Avoid double-freeing the umem. */