drm/i915/ttm: add unmap_virtual callback

Ensure we call ttm_bo_unmap_virtual when releasing the pages.
Importantly this should now handle the ttm swapping case, and all other
places that already call into i915_ttm_move_notify().

v2: fix up the selftest

Fixes: cf3e3e86 ("drm/i915: Use ttm mmap handling for ttm bo's.")
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220106174910.280616-3-matthew.auld@intel.com
(cherry picked from commit 903e0387)
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

drivers/gpu/drm/i915/gem/i915_gem_mman.c

@@ -538,6 +538,9 @@ void i915_gem_object_release_mmap_offset(struct drm_i915_gem_object *obj)
 {
 	struct i915_mmap_offset *mmo, *mn;
 
+	if (obj->ops->unmap_virtual)
+		obj->ops->unmap_virtual(obj);
+
 	spin_lock(&obj->mmo.lock);
 	rbtree_postorder_for_each_entry_safe(mmo, mn,
 					     &obj->mmo.offsets, offset) {

drivers/gpu/drm/i915/gem/i915_gem_object_types.h

@@ -67,6 +67,7 @@ struct drm_i915_gem_object_ops {
 	int (*pwrite)(struct drm_i915_gem_object *obj,
 		      const struct drm_i915_gem_pwrite *arg);
 	u64 (*mmap_offset)(struct drm_i915_gem_object *obj);
+	void (*unmap_virtual)(struct drm_i915_gem_object *obj);
 
 	int (*dmabuf_export)(struct drm_i915_gem_object *obj);
 

drivers/gpu/drm/i915/gem/i915_gem_ttm.c

@@ -950,6 +950,11 @@ static u64 i915_ttm_mmap_offset(struct drm_i915_gem_object *obj)
 	return drm_vma_node_offset_addr(&obj->base.vma_node);
 }
 
+static void i915_ttm_unmap_virtual(struct drm_i915_gem_object *obj)
+{
+	ttm_bo_unmap_virtual(i915_gem_to_ttm(obj));
+}
+
 static const struct drm_i915_gem_object_ops i915_gem_ttm_obj_ops = {
 	.name = "i915_gem_object_ttm",
 	.flags = I915_GEM_OBJECT_IS_SHRINKABLE |
@@ -965,6 +970,7 @@ static const struct drm_i915_gem_object_ops i915_gem_ttm_obj_ops = {
 	.migrate = i915_ttm_migrate,
 
 	.mmap_offset = i915_ttm_mmap_offset,
+	.unmap_virtual = i915_ttm_unmap_virtual,
 	.mmap_ops = &vm_ops_ttm,
 };
 

drivers/gpu/drm/i915/gem/selftests/i915_gem_mman.c

@@ -1368,21 +1368,11 @@ static int __igt_mmap_revoke(struct drm_i915_private *i915,
 		}
 	}
 
-	if (!obj->ops->mmap_ops) {
 	err = check_absent(addr, obj->base.size);
 	if (err) {
 		pr_err("%s: was not absent\n", obj->mm.region->name);
 		goto out_unmap;
 	}
-	} else {
-		/* ttm allows access to evicted regions by design */
-
-		err = check_present(addr, obj->base.size);
-		if (err) {
-			pr_err("%s: was not present\n", obj->mm.region->name);
-			goto out_unmap;
-		}
-	}
 
 out_unmap:
 	vm_munmap(addr, obj->base.size);