diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
index 57cc68177f09..67f64bd1058f 100644
--- a/drivers/gpu/drm/drm_atomic.c
+++ b/drivers/gpu/drm/drm_atomic.c
@@ -56,6 +56,11 @@ drm_atomic_state_alloc(struct drm_device *dev)
 	if (!state)
 		return NULL;
 
+	/* TODO legacy paths should maybe do a better job about
+	 * setting this appropriately?
+	 */
+	state->allow_modeset = true;
+
 	state->num_connector = ACCESS_ONCE(dev->mode_config.num_connector);
 
 	state->crtcs = kcalloc(dev->mode_config.num_crtc,
@@ -1003,6 +1008,22 @@ int drm_atomic_check_only(struct drm_atomic_state *state)
 	if (config->funcs->atomic_check)
 		ret = config->funcs->atomic_check(state->dev, state);
 
+	if (!state->allow_modeset) {
+		for (i = 0; i < ncrtcs; i++) {
+			struct drm_crtc *crtc = state->crtcs[i];
+			struct drm_crtc_state *crtc_state = state->crtc_states[i];
+
+			if (!crtc)
+				continue;
+
+			if (crtc_state->mode_changed) {
+				DRM_DEBUG_KMS("[CRTC:%d] requires full modeset\n",
+					      crtc->base.id);
+				return -EINVAL;
+			}
+		}
+	}
+
 	return ret;
 }
 EXPORT_SYMBOL(drm_atomic_check_only);
@@ -1068,3 +1089,313 @@ int drm_atomic_async_commit(struct drm_atomic_state *state)
 	return config->funcs->atomic_commit(state->dev, state, true);
 }
 EXPORT_SYMBOL(drm_atomic_async_commit);
+
+/*
+ * The big monstor ioctl
+ */
+
+static struct drm_pending_vblank_event *create_vblank_event(
+		struct drm_device *dev, struct drm_file *file_priv, uint64_t user_data)
+{
+	struct drm_pending_vblank_event *e = NULL;
+	unsigned long flags;
+
+	spin_lock_irqsave(&dev->event_lock, flags);
+	if (file_priv->event_space < sizeof e->event) {
+		spin_unlock_irqrestore(&dev->event_lock, flags);
+		goto out;
+	}
+	file_priv->event_space -= sizeof e->event;
+	spin_unlock_irqrestore(&dev->event_lock, flags);
+
+	e = kzalloc(sizeof *e, GFP_KERNEL);
+	if (e == NULL) {
+		spin_lock_irqsave(&dev->event_lock, flags);
+		file_priv->event_space += sizeof e->event;
+		spin_unlock_irqrestore(&dev->event_lock, flags);
+		goto out;
+	}
+
+	e->event.base.type = DRM_EVENT_FLIP_COMPLETE;
+	e->event.base.length = sizeof e->event;
+	e->event.user_data = user_data;
+	e->base.event = &e->event.base;
+	e->base.file_priv = file_priv;
+	e->base.destroy = (void (*) (struct drm_pending_event *)) kfree;
+
+out:
+	return e;
+}
+
+static void destroy_vblank_event(struct drm_device *dev,
+		struct drm_file *file_priv, struct drm_pending_vblank_event *e)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&dev->event_lock, flags);
+	file_priv->event_space += sizeof e->event;
+	spin_unlock_irqrestore(&dev->event_lock, flags);
+	kfree(e);
+}
+
+static int atomic_set_prop(struct drm_atomic_state *state,
+		struct drm_mode_object *obj, struct drm_property *prop,
+		uint64_t prop_value)
+{
+	struct drm_mode_object *ref;
+	int ret;
+
+	if (!drm_property_change_valid_get(prop, prop_value, &ref))
+		return -EINVAL;
+
+	switch (obj->type) {
+	case DRM_MODE_OBJECT_CONNECTOR: {
+		struct drm_connector *connector = obj_to_connector(obj);
+		struct drm_connector_state *connector_state;
+
+		connector_state = drm_atomic_get_connector_state(state, connector);
+		if (IS_ERR(connector_state)) {
+			ret = PTR_ERR(connector_state);
+			break;
+		}
+
+		ret = drm_atomic_connector_set_property(connector,
+				connector_state, prop, prop_value);
+		break;
+	}
+	case DRM_MODE_OBJECT_CRTC: {
+		struct drm_crtc *crtc = obj_to_crtc(obj);
+		struct drm_crtc_state *crtc_state;
+
+		crtc_state = drm_atomic_get_crtc_state(state, crtc);
+		if (IS_ERR(crtc_state)) {
+			ret = PTR_ERR(crtc_state);
+			break;
+		}
+
+		ret = drm_atomic_crtc_set_property(crtc,
+				crtc_state, prop, prop_value);
+		break;
+	}
+	case DRM_MODE_OBJECT_PLANE: {
+		struct drm_plane *plane = obj_to_plane(obj);
+		struct drm_plane_state *plane_state;
+
+		plane_state = drm_atomic_get_plane_state(state, plane);
+		if (IS_ERR(plane_state)) {
+			ret = PTR_ERR(plane_state);
+			break;
+		}
+
+		ret = drm_atomic_plane_set_property(plane,
+				plane_state, prop, prop_value);
+		break;
+	}
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	drm_property_change_valid_put(prop, ref);
+	return ret;
+}
+
+int drm_mode_atomic_ioctl(struct drm_device *dev,
+			  void *data, struct drm_file *file_priv)
+{
+	struct drm_mode_atomic *arg = data;
+	uint32_t __user *objs_ptr = (uint32_t __user *)(unsigned long)(arg->objs_ptr);
+	uint32_t __user *count_props_ptr = (uint32_t __user *)(unsigned long)(arg->count_props_ptr);
+	uint32_t __user *props_ptr = (uint32_t __user *)(unsigned long)(arg->props_ptr);
+	uint64_t __user *prop_values_ptr = (uint64_t __user *)(unsigned long)(arg->prop_values_ptr);
+	unsigned int copied_objs, copied_props;
+	struct drm_atomic_state *state;
+	struct drm_modeset_acquire_ctx ctx;
+	struct drm_plane *plane;
+	unsigned plane_mask = 0;
+	int ret = 0;
+	unsigned int i, j;
+
+	/* disallow for drivers not supporting atomic: */
+	if (!drm_core_check_feature(dev, DRIVER_ATOMIC))
+		return -EINVAL;
+
+	/* disallow for userspace that has not enabled atomic cap (even
+	 * though this may be a bit overkill, since legacy userspace
+	 * wouldn't know how to call this ioctl)
+	 */
+	if (!file_priv->atomic)
+		return -EINVAL;
+
+	if (arg->flags & ~DRM_MODE_ATOMIC_FLAGS)
+		return -EINVAL;
+
+	if (arg->reserved)
+		return -EINVAL;
+
+	if ((arg->flags & DRM_MODE_PAGE_FLIP_ASYNC) &&
+			!dev->mode_config.async_page_flip)
+		return -EINVAL;
+
+	/* can't test and expect an event at the same time. */
+	if ((arg->flags & DRM_MODE_ATOMIC_TEST_ONLY) &&
+			(arg->flags & DRM_MODE_PAGE_FLIP_EVENT))
+		return -EINVAL;
+
+	drm_modeset_acquire_init(&ctx, 0);
+
+	state = drm_atomic_state_alloc(dev);
+	if (!state)
+		return -ENOMEM;
+
+	state->acquire_ctx = &ctx;
+	state->allow_modeset = !!(arg->flags & DRM_MODE_ATOMIC_ALLOW_MODESET);
+
+retry:
+	copied_objs = 0;
+	copied_props = 0;
+
+	for (i = 0; i < arg->count_objs; i++) {
+		uint32_t obj_id, count_props;
+		struct drm_mode_object *obj;
+
+		if (get_user(obj_id, objs_ptr + copied_objs)) {
+			ret = -EFAULT;
+			goto fail;
+		}
+
+		obj = drm_mode_object_find(dev, obj_id, DRM_MODE_OBJECT_ANY);
+		if (!obj || !obj->properties) {
+			ret = -ENOENT;
+			goto fail;
+		}
+
+		if (obj->type == DRM_MODE_OBJECT_PLANE) {
+			plane = obj_to_plane(obj);
+			plane_mask |= (1 << drm_plane_index(plane));
+			plane->old_fb = plane->fb;
+		}
+
+		if (get_user(count_props, count_props_ptr + copied_objs)) {
+			ret = -EFAULT;
+			goto fail;
+		}
+
+		copied_objs++;
+
+		for (j = 0; j < count_props; j++) {
+			uint32_t prop_id;
+			uint64_t prop_value;
+			struct drm_property *prop;
+
+			if (get_user(prop_id, props_ptr + copied_props)) {
+				ret = -EFAULT;
+				goto fail;
+			}
+
+			prop = drm_property_find(dev, prop_id);
+			if (!prop) {
+				ret = -ENOENT;
+				goto fail;
+			}
+
+			if (get_user(prop_value, prop_values_ptr + copied_props)) {
+				ret = -EFAULT;
+				goto fail;
+			}
+
+			ret = atomic_set_prop(state, obj, prop, prop_value);
+			if (ret)
+				goto fail;
+
+			copied_props++;
+		}
+	}
+
+	if (arg->flags & DRM_MODE_PAGE_FLIP_EVENT) {
+		int ncrtcs = dev->mode_config.num_crtc;
+
+		for (i = 0; i < ncrtcs; i++) {
+			struct drm_crtc_state *crtc_state = state->crtc_states[i];
+			struct drm_pending_vblank_event *e;
+
+			if (!crtc_state)
+				continue;
+
+			e = create_vblank_event(dev, file_priv, arg->user_data);
+			if (!e) {
+				ret = -ENOMEM;
+				goto fail;
+			}
+
+			crtc_state->event = e;
+		}
+	}
+
+	if (arg->flags & DRM_MODE_ATOMIC_TEST_ONLY) {
+		ret = drm_atomic_check_only(state);
+		/* _check_only() does not free state, unlike _commit() */
+		drm_atomic_state_free(state);
+	} else if (arg->flags & DRM_MODE_ATOMIC_NONBLOCK) {
+		ret = drm_atomic_async_commit(state);
+	} else {
+		ret = drm_atomic_commit(state);
+	}
+
+	/* if succeeded, fixup legacy plane crtc/fb ptrs before dropping
+	 * locks (ie. while it is still safe to deref plane->state).  We
+	 * need to do this here because the driver entry points cannot
+	 * distinguish between legacy and atomic ioctls.
+	 */
+	drm_for_each_plane_mask(plane, dev, plane_mask) {
+		if (ret == 0) {
+			struct drm_framebuffer *new_fb = plane->state->fb;
+			if (new_fb)
+				drm_framebuffer_reference(new_fb);
+			plane->fb = new_fb;
+			plane->crtc = plane->state->crtc;
+		} else {
+			plane->old_fb = NULL;
+		}
+		if (plane->old_fb) {
+			drm_framebuffer_unreference(plane->old_fb);
+			plane->old_fb = NULL;
+		}
+	}
+
+	drm_modeset_drop_locks(&ctx);
+	drm_modeset_acquire_fini(&ctx);
+
+	return ret;
+
+fail:
+	if (ret == -EDEADLK)
+		goto backoff;
+
+	if (arg->flags & DRM_MODE_PAGE_FLIP_EVENT) {
+		int ncrtcs = dev->mode_config.num_crtc;
+
+		for (i = 0; i < ncrtcs; i++) {
+			struct drm_crtc_state *crtc_state = state->crtc_states[i];
+
+			if (!crtc_state)
+				continue;
+
+			destroy_vblank_event(dev, file_priv, crtc_state->event);
+			crtc_state->event = NULL;
+		}
+	}
+
+	drm_atomic_state_free(state);
+
+	drm_modeset_drop_locks(&ctx);
+	drm_modeset_acquire_fini(&ctx);
+
+	return ret;
+
+backoff:
+	drm_atomic_state_clear(state);
+	drm_modeset_backoff(&ctx);
+
+	goto retry;
+}
diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
index 3cb1fa09ac9e..20596423d52d 100644
--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -4303,7 +4303,7 @@ EXPORT_SYMBOL(drm_mode_connector_update_edid_property);
  * object to which the property is attached has a chance to take it's own
  * reference).
  */
-static bool drm_property_change_valid_get(struct drm_property *property,
+bool drm_property_change_valid_get(struct drm_property *property,
 					 uint64_t value, struct drm_mode_object **ref)
 {
 	int i;
@@ -4365,7 +4365,7 @@ static bool drm_property_change_valid_get(struct drm_property *property,
 	return false;
 }
 
-static void drm_property_change_valid_put(struct drm_property *property,
+void drm_property_change_valid_put(struct drm_property *property,
 		struct drm_mode_object *ref)
 {
 	if (!ref)
diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c
index adc822312f6c..a28c0abd1a38 100644
--- a/drivers/gpu/drm/drm_ioctl.c
+++ b/drivers/gpu/drm/drm_ioctl.c
@@ -630,6 +630,7 @@ static const struct drm_ioctl_desc drm_ioctls[] = {
 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_GETPROPERTIES, drm_mode_obj_get_properties_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_SETPROPERTY, drm_mode_obj_set_property_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR2, drm_mode_cursor2_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
+	DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATOMIC, drm_mode_atomic_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 };
 
 #define DRM_CORE_IOCTL_COUNT	ARRAY_SIZE( drm_ioctls )
diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index fc4767fa723b..1dcfb685d15f 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -902,7 +902,7 @@ struct drm_bridge {
 /**
  * struct struct drm_atomic_state - the global state object for atomic updates
  * @dev: parent DRM device
- * @flags: state flags like async update
+ * @allow_modeset: allow full modeset
  * @planes: pointer to array of plane pointers
  * @plane_states: pointer to array of plane states pointers
  * @crtcs: pointer to array of CRTC pointers
@@ -914,7 +914,7 @@ struct drm_bridge {
  */
 struct drm_atomic_state {
 	struct drm_device *dev;
-	uint32_t flags;
+	bool allow_modeset : 1;
 	struct drm_plane **planes;
 	struct drm_plane_state **plane_states;
 	struct drm_crtc **crtcs;
@@ -1346,6 +1346,10 @@ extern int drm_mode_create_scaling_mode_property(struct drm_device *dev);
 extern int drm_mode_create_aspect_ratio_property(struct drm_device *dev);
 extern int drm_mode_create_dirty_info_property(struct drm_device *dev);
 extern int drm_mode_create_suggested_offset_properties(struct drm_device *dev);
+extern bool drm_property_change_valid_get(struct drm_property *property,
+					 uint64_t value, struct drm_mode_object **ref);
+extern void drm_property_change_valid_put(struct drm_property *property,
+		struct drm_mode_object *ref);
 
 extern int drm_mode_connector_attach_encoder(struct drm_connector *connector,
 					     struct drm_encoder *encoder);
@@ -1437,6 +1441,8 @@ extern int drm_mode_obj_set_property_ioctl(struct drm_device *dev, void *data,
 extern int drm_mode_plane_set_obj_prop(struct drm_plane *plane,
 				       struct drm_property *property,
 				       uint64_t value);
+extern int drm_mode_atomic_ioctl(struct drm_device *dev,
+				 void *data, struct drm_file *file_priv);
 
 extern void drm_fb_get_bpp_depth(uint32_t format, unsigned int *depth,
 				 int *bpp);
diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h
index f7b2baf7ecb2..01b2d6d0e355 100644
--- a/include/uapi/drm/drm.h
+++ b/include/uapi/drm/drm.h
@@ -784,6 +784,7 @@ struct drm_prime_handle {
 #define DRM_IOCTL_MODE_OBJ_GETPROPERTIES	DRM_IOWR(0xB9, struct drm_mode_obj_get_properties)
 #define DRM_IOCTL_MODE_OBJ_SETPROPERTY	DRM_IOWR(0xBA, struct drm_mode_obj_set_property)
 #define DRM_IOCTL_MODE_CURSOR2		DRM_IOWR(0xBB, struct drm_mode_cursor2)
+#define DRM_IOCTL_MODE_ATOMIC		DRM_IOWR(0xBC, struct drm_mode_atomic)
 
 /**
  * Device specific ioctls should only be in their respective headers
diff --git a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h
index b8f9c0f2e7fe..ca788e01dab2 100644
--- a/include/uapi/drm/drm_mode.h
+++ b/include/uapi/drm/drm_mode.h
@@ -526,4 +526,27 @@ struct drm_mode_destroy_dumb {
 	uint32_t handle;
 };
 
+/* page-flip flags are valid, plus: */
+#define DRM_MODE_ATOMIC_TEST_ONLY 0x0100
+#define DRM_MODE_ATOMIC_NONBLOCK  0x0200
+#define DRM_MODE_ATOMIC_ALLOW_MODESET 0x0400
+
+#define DRM_MODE_ATOMIC_FLAGS (\
+		DRM_MODE_PAGE_FLIP_EVENT |\
+		DRM_MODE_PAGE_FLIP_ASYNC |\
+		DRM_MODE_ATOMIC_TEST_ONLY |\
+		DRM_MODE_ATOMIC_NONBLOCK |\
+		DRM_MODE_ATOMIC_ALLOW_MODESET)
+
+struct drm_mode_atomic {
+	__u32 flags;
+	__u32 count_objs;
+	__u64 objs_ptr;
+	__u64 count_props_ptr;
+	__u64 props_ptr;
+	__u64 prop_values_ptr;
+	__u64 reserved;
+	__u64 user_data;
+};
+
 #endif