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
  ...

4 files changed, 39 insertions, 124 deletions

diff --git a/drivers/gpu/drm/radeon/radeon.h b/drivers/gpu/drm/radeon/radeon.h
index 05b88491ccb9..d59b004f6695 100644
--- a/drivers/gpu/drm/radeon/radeon.h
+++ b/drivers/gpu/drm/radeon/radeon.h
@@ -2449,9 +2449,6 @@ struct radeon_device {
 	/* tracking pinned memory */
 	u64 vram_pin_size;
 	u64 gart_pin_size;
-
-	struct mutex	mn_lock;
-	DECLARE_HASHTABLE(mn_hash, 7);
 };
 
 bool radeon_is_px(struct drm_device *dev);
diff --git a/drivers/gpu/drm/radeon/radeon_device.c b/drivers/gpu/drm/radeon/radeon_device.c
index 88eb7cb522bb..5d017f0aec66 100644
--- a/drivers/gpu/drm/radeon/radeon_device.c
+++ b/drivers/gpu/drm/radeon/radeon_device.c
@@ -1325,8 +1325,6 @@ int radeon_device_init(struct radeon_device *rdev,
 	init_rwsem(&rdev->pm.mclk_lock);
 	init_rwsem(&rdev->exclusive_lock);
 	init_waitqueue_head(&rdev->irq.vblank_queue);
-	mutex_init(&rdev->mn_lock);
-	hash_init(rdev->mn_hash);
 	r = radeon_gem_init(rdev);
 	if (r)
 		return r;
diff --git a/drivers/gpu/drm/radeon/radeon_drv.c b/drivers/gpu/drm/radeon/radeon_drv.c
index 5838162f687f..431e6b64b77d 100644
--- a/drivers/gpu/drm/radeon/radeon_drv.c
+++ b/drivers/gpu/drm/radeon/radeon_drv.c
@@ -35,6 +35,7 @@
 #include <linux/module.h>
 #include <linux/pm_runtime.h>
 #include <linux/vga_switcheroo.h>
+#include <linux/mmu_notifier.h>
 
 #include <drm/drm_crtc_helper.h>
 #include <drm/drm_drv.h>
@@ -623,6 +624,7 @@ static void __exit radeon_exit(void)
 {
 	pci_unregister_driver(pdriver);
 	radeon_unregister_atpx_handler();
+	mmu_notifier_synchronize();
 }
 
 module_init(radeon_init);
diff --git a/drivers/gpu/drm/radeon/radeon_mn.c b/drivers/gpu/drm/radeon/radeon_mn.c
index 6902f998ede9..dbab9a3a969b 100644
--- a/drivers/gpu/drm/radeon/radeon_mn.c
+++ b/drivers/gpu/drm/radeon/radeon_mn.c
@@ -37,17 +37,8 @@
 #include "radeon.h"
 
 struct radeon_mn {
-	/* constant after initialisation */
-	struct radeon_device	*rdev;
-	struct mm_struct	*mm;
 	struct mmu_notifier	mn;
 
-	/* only used on destruction */
-	struct work_struct	work;
-
-	/* protected by rdev->mn_lock */
-	struct hlist_node	node;
-
 	/* objects protected by lock */
 	struct mutex		lock;
 	struct rb_root_cached	objects;
@@ -59,55 +50,6 @@ struct radeon_mn_node {
 };
 
 /**
- * radeon_mn_destroy - destroy the rmn
- *
- * @work: previously sheduled work item
- *
- * Lazy destroys the notifier from a work item
- */
-static void radeon_mn_destroy(struct work_struct *work)
-{
-	struct radeon_mn *rmn = container_of(work, struct radeon_mn, work);
-	struct radeon_device *rdev = rmn->rdev;
-	struct radeon_mn_node *node, *next_node;
-	struct radeon_bo *bo, *next_bo;
-
-	mutex_lock(&rdev->mn_lock);
-	mutex_lock(&rmn->lock);
-	hash_del(&rmn->node);
-	rbtree_postorder_for_each_entry_safe(node, next_node,
-					     &rmn->objects.rb_root, it.rb) {
-
-		interval_tree_remove(&node->it, &rmn->objects);
-		list_for_each_entry_safe(bo, next_bo, &node->bos, mn_list) {
-			bo->mn = NULL;
-			list_del_init(&bo->mn_list);
-		}
-		kfree(node);
-	}
-	mutex_unlock(&rmn->lock);
-	mutex_unlock(&rdev->mn_lock);
-	mmu_notifier_unregister(&rmn->mn, rmn->mm);
-	kfree(rmn);
-}
-
-/**
- * radeon_mn_release - callback to notify about mm destruction
- *
- * @mn: our notifier
- * @mn: the mm this callback is about
- *
- * Shedule a work item to lazy destroy our notifier.
- */
-static void radeon_mn_release(struct mmu_notifier *mn,
-			      struct mm_struct *mm)
-{
-	struct radeon_mn *rmn = container_of(mn, struct radeon_mn, mn);
-	INIT_WORK(&rmn->work, radeon_mn_destroy);
-	schedule_work(&rmn->work);
-}
-
-/**
  * radeon_mn_invalidate_range_start - callback to notify about mm change
  *
  * @mn: our notifier
@@ -183,65 +125,44 @@ out_unlock:
 	return ret;
 }
 
-static const struct mmu_notifier_ops radeon_mn_ops = {
-	.release = radeon_mn_release,
-	.invalidate_range_start = radeon_mn_invalidate_range_start,
-};
+static void radeon_mn_release(struct mmu_notifier *mn, struct mm_struct *mm)
+{
+	struct mmu_notifier_range range = {
+		.mm = mm,
+		.start = 0,
+		.end = ULONG_MAX,
+		.flags = 0,
+		.event = MMU_NOTIFY_UNMAP,
+	};
+
+	radeon_mn_invalidate_range_start(mn, &range);
+}
 
-/**
- * radeon_mn_get - create notifier context
- *
- * @rdev: radeon device pointer
- *
- * Creates a notifier context for current->mm.
- */
-static struct radeon_mn *radeon_mn_get(struct radeon_device *rdev)
+static struct mmu_notifier *radeon_mn_alloc_notifier(struct mm_struct *mm)
 {
-	struct mm_struct *mm = current->mm;
 	struct radeon_mn *rmn;
-	int r;
-
-	if (down_write_killable(&mm->mmap_sem))
-		return ERR_PTR(-EINTR);
-
-	mutex_lock(&rdev->mn_lock);
-
-	hash_for_each_possible(rdev->mn_hash, rmn, node, (unsigned long)mm)
-		if (rmn->mm == mm)
-			goto release_locks;
 
 	rmn = kzalloc(sizeof(*rmn), GFP_KERNEL);
-	if (!rmn) {
-		rmn = ERR_PTR(-ENOMEM);
-		goto release_locks;
-	}
+	if (!rmn)
+		return ERR_PTR(-ENOMEM);
 
-	rmn->rdev = rdev;
-	rmn->mm = mm;
-	rmn->mn.ops = &radeon_mn_ops;
 	mutex_init(&rmn->lock);
 	rmn->objects = RB_ROOT_CACHED;
-	
-	r = __mmu_notifier_register(&rmn->mn, mm);
-	if (r)
-		goto free_rmn;
-
-	hash_add(rdev->mn_hash, &rmn->node, (unsigned long)mm);
-
-release_locks:
-	mutex_unlock(&rdev->mn_lock);
-	up_write(&mm->mmap_sem);
-
-	return rmn;
-
-free_rmn:
-	mutex_unlock(&rdev->mn_lock);
-	up_write(&mm->mmap_sem);
-	kfree(rmn);
+	return &rmn->mn;
+}
 
-	return ERR_PTR(r);
+static void radeon_mn_free_notifier(struct mmu_notifier *mn)
+{
+	kfree(container_of(mn, struct radeon_mn, mn));
 }
 
+static const struct mmu_notifier_ops radeon_mn_ops = {
+	.release = radeon_mn_release,
+	.invalidate_range_start = radeon_mn_invalidate_range_start,
+	.alloc_notifier = radeon_mn_alloc_notifier,
+	.free_notifier = radeon_mn_free_notifier,
+};
+
 /**
  * radeon_mn_register - register a BO for notifier updates
  *
@@ -254,15 +175,16 @@ free_rmn:
 int radeon_mn_register(struct radeon_bo *bo, unsigned long addr)
 {
 	unsigned long end = addr + radeon_bo_size(bo) - 1;
-	struct radeon_device *rdev = bo->rdev;
+	struct mmu_notifier *mn;
 	struct radeon_mn *rmn;
 	struct radeon_mn_node *node = NULL;
 	struct list_head bos;
 	struct interval_tree_node *it;
 
-	rmn = radeon_mn_get(rdev);
-	if (IS_ERR(rmn))
-		return PTR_ERR(rmn);
+	mn = mmu_notifier_get(&radeon_mn_ops, current->mm);
+	if (IS_ERR(mn))
+		return PTR_ERR(mn);
+	rmn = container_of(mn, struct radeon_mn, mn);
 
 	INIT_LIST_HEAD(&bos);
 
@@ -309,22 +231,16 @@ int radeon_mn_register(struct radeon_bo *bo, unsigned long addr)
  */
 void radeon_mn_unregister(struct radeon_bo *bo)
 {
-	struct radeon_device *rdev = bo->rdev;
-	struct radeon_mn *rmn;
+	struct radeon_mn *rmn = bo->mn;
 	struct list_head *head;
 
-	mutex_lock(&rdev->mn_lock);
-	rmn = bo->mn;
-	if (rmn == NULL) {
-		mutex_unlock(&rdev->mn_lock);
+	if (!rmn)
 		return;
-	}
 
 	mutex_lock(&rmn->lock);
 	/* save the next list entry for later */
 	head = bo->mn_list.next;
 
-	bo->mn = NULL;
 	list_del(&bo->mn_list);
 
 	if (list_empty(head)) {
@@ -335,5 +251,7 @@ void radeon_mn_unregister(struct radeon_bo *bo)
 	}
 
 	mutex_unlock(&rmn->lock);
-	mutex_unlock(&rdev->mn_lock);
+
+	mmu_notifier_put(&rmn->mn);
+	bo->mn = NULL;
 }