Merge tag 'topic/connector-locking-2015-07-23' of git://anongit.freedesktop.org/drm-intel into drm-next

connector hotplug locking cleanup and fixes to make it save against
atomic. Note that because of depencies this is based on top of the
drm-intel-next pull, so that one needs to go in before this one.

I've also thrown in the mode_group removal on top since it's defunct,
never worked really, no one seems to care and the code can be resurrected
easily.

* tag 'topic/connector-locking-2015-07-23' of git://anongit.freedesktop.org/drm-intel:
drm: gc now dead mode_group code
drm: Stop filtering according to mode_group in getresources
drm: Roll out drm_for_each_{plane,crtc,encoder}
drm/cma-helper: Fix locking in drm_fb_cma_debugfs_show
drm: Roll out drm_for_each_connector more
drm: Amend connector list locking rules
drm/radeon: Take all modeset locks for DP MST hotplug
drm/i915: Take all modeset locks for DP MST hotplug
drm: Check locking in drm_for_each_fb
drm/i915: Use drm_for_each_fb in i915_debugfs.c
drm: Check locking in drm_for_each_connector
drm/fbdev-helper: Grab mode_config.mutex in drm_fb_helper_single_add_all_connectors
drm/probe-helper: Grab mode_config.mutex in poll_init/enable
drm: Add modeset object iterators
drm: Simplify drm_for_each_legacy_plane arguments

drivers/gpu/drm/drm_atomic.c

···
 	 * Changed connectors are already in @state, so only need to look at the
 	 * current configuration.
 	 */
-	list_for_each_entry(connector, &config->connector_list, head) {
+	drm_for_each_connector(connector, state->dev) {
 		if (connector->state->crtc != crtc)
 			continue;
 

drivers/gpu/drm/drm_atomic_helper.c

···
 
 	WARN_ON(!drm_modeset_is_locked(&config->connection_mutex));
 
-	list_for_each_entry(connector, &config->connector_list, head) {
+	drm_for_each_connector(connector, dev) {
 		if (connector->state->best_encoder != encoder)
 			continue;
 
···
 
 	WARN_ON(!drm_modeset_is_locked(&config->connection_mutex));
 
-	list_for_each_entry(tmp_connector, &config->connector_list, head) {
+	drm_for_each_connector(tmp_connector, connector->dev) {
 		if (tmp_connector->state->crtc != crtc)
 			continue;
 

drivers/gpu/drm/drm_crtc.c

···
 	if (atomic_read(&fb->refcount.refcount) > 1) {
 		drm_modeset_lock_all(dev);
 		/* remove from any CRTC */
-		list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
+		drm_for_each_crtc(crtc, dev) {
 			if (crtc->primary->fb == fb) {
 				/* should turn off the crtc */
 				memset(&set, 0, sizeof(struct drm_mode_set));
···
 			}
 		}
 
-		list_for_each_entry(plane, &dev->mode_config.plane_list, head) {
+		drm_for_each_plane(plane, dev) {
 			if (plane->fb == fb)
 				drm_plane_force_disable(plane);
 		}
···
 	unsigned int index = 0;
 	struct drm_crtc *tmp;
 
-	list_for_each_entry(tmp, &crtc->dev->mode_config.crtc_list, head) {
+	drm_for_each_crtc(tmp, crtc->dev) {
 		if (tmp == crtc)
 			return index;
 
···
 
 	WARN_ON(!drm_modeset_is_locked(&config->connection_mutex));
 
-	list_for_each_entry(tmp, &connector->dev->mode_config.connector_list, head) {
+	drm_for_each_connector(tmp, connector->dev) {
 		if (tmp == connector)
 			return index;
 
···
 {
 	struct drm_connector *connector;
 
-	/* taking the mode config mutex ends up in a clash with sysfs */
+	/* FIXME: taking the mode config mutex ends up in a clash with sysfs */
 	list_for_each_entry(connector, &dev->mode_config.connector_list, head)
 		drm_connector_unregister(connector);
 
···
 	unsigned int index = 0;
 	struct drm_plane *tmp;
 
-	list_for_each_entry(tmp, &plane->dev->mode_config.plane_list, head) {
+	drm_for_each_plane(tmp, plane->dev) {
 		if (tmp == plane)
 			return index;
 
···
 	struct drm_plane *plane;
 	unsigned int i = 0;
 
-	list_for_each_entry(plane, &dev->mode_config.plane_list, head) {
+	drm_for_each_plane(plane, dev) {
 		if (i == idx)
 			return plane;
 		i++;
···
 }
 EXPORT_SYMBOL(drm_mode_create_suggested_offset_properties);
 
-static int drm_mode_group_init(struct drm_device *dev, struct drm_mode_group *group)
-{
-	uint32_t total_objects = 0;
-
-	total_objects += dev->mode_config.num_crtc;
-	total_objects += dev->mode_config.num_connector;
-	total_objects += dev->mode_config.num_encoder;
-
-	group->id_list = kcalloc(total_objects, sizeof(uint32_t), GFP_KERNEL);
-	if (!group->id_list)
-		return -ENOMEM;
-
-	group->num_crtcs = 0;
-	group->num_connectors = 0;
-	group->num_encoders = 0;
-	return 0;
-}
-
-void drm_mode_group_destroy(struct drm_mode_group *group)
-{
-	kfree(group->id_list);
-	group->id_list = NULL;
-}
-
-/*
- * NOTE: Driver's shouldn't ever call drm_mode_group_init_legacy_group - it is
- * the drm core's responsibility to set up mode control groups.
- */
-int drm_mode_group_init_legacy_group(struct drm_device *dev,
-				     struct drm_mode_group *group)
-{
-	struct drm_crtc *crtc;
-	struct drm_encoder *encoder;
-	struct drm_connector *connector;
-	int ret;
-
-	ret = drm_mode_group_init(dev, group);
-	if (ret)
-		return ret;
-
-	list_for_each_entry(crtc, &dev->mode_config.crtc_list, head)
-		group->id_list[group->num_crtcs++] = crtc->base.id;
-
-	list_for_each_entry(encoder, &dev->mode_config.encoder_list, head)
-		group->id_list[group->num_crtcs + group->num_encoders++] =
-		encoder->base.id;
-
-	list_for_each_entry(connector, &dev->mode_config.connector_list, head)
-		group->id_list[group->num_crtcs + group->num_encoders +
-			       group->num_connectors++] = connector->base.id;
-
-	return 0;
-}
-EXPORT_SYMBOL(drm_mode_group_init_legacy_group);
-
-void drm_reinit_primary_mode_group(struct drm_device *dev)
-{
-	drm_modeset_lock_all(dev);
-	drm_mode_group_destroy(&dev->primary->mode_group);
-	drm_mode_group_init_legacy_group(dev, &dev->primary->mode_group);
-	drm_modeset_unlock_all(dev);
-}
-EXPORT_SYMBOL(drm_reinit_primary_mode_group);
-
 /**
  * drm_mode_getresources - get graphics configuration
  * @dev: drm device for the ioctl
···
 	int crtc_count = 0;
 	int fb_count = 0;
 	int encoder_count = 0;
-	int copied = 0, i;
+	int copied = 0;
 	uint32_t __user *fb_id;
 	uint32_t __user *crtc_id;
 	uint32_t __user *connector_id;
 	uint32_t __user *encoder_id;
-	struct drm_mode_group *mode_group;
 
 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
 		return -EINVAL;
···
 	/* mode_config.mutex protects the connector list against e.g. DP MST
 	 * connector hot-adding. CRTC/Plane lists are invariant. */
 	mutex_lock(&dev->mode_config.mutex);
-	if (!drm_is_primary_client(file_priv)) {
+	drm_for_each_crtc(crtc, dev)
+		crtc_count++;
 
-		mode_group = NULL;
-		list_for_each(lh, &dev->mode_config.crtc_list)
-			crtc_count++;
+	drm_for_each_connector(connector, dev)
+		connector_count++;
 
-		list_for_each(lh, &dev->mode_config.connector_list)
-			connector_count++;
-
-		list_for_each(lh, &dev->mode_config.encoder_list)
-			encoder_count++;
-	} else {
-
-		mode_group = &file_priv->master->minor->mode_group;
-		crtc_count = mode_group->num_crtcs;
-		connector_count = mode_group->num_connectors;
-		encoder_count = mode_group->num_encoders;
-	}
+	drm_for_each_encoder(encoder, dev)
+		encoder_count++;
 
 	card_res->max_height = dev->mode_config.max_height;
 	card_res->min_height = dev->mode_config.min_height;
···
 	if (card_res->count_crtcs >= crtc_count) {
 		copied = 0;
 		crtc_id = (uint32_t __user *)(unsigned long)card_res->crtc_id_ptr;
-		if (!mode_group) {
-			list_for_each_entry(crtc, &dev->mode_config.crtc_list,
-					    head) {
-				DRM_DEBUG_KMS("[CRTC:%d]\n", crtc->base.id);
-				if (put_user(crtc->base.id, crtc_id + copied)) {
-					ret = -EFAULT;
-					goto out;
-				}
-				copied++;
+		drm_for_each_crtc(crtc, dev) {
+			DRM_DEBUG_KMS("[CRTC:%d]\n", crtc->base.id);
+			if (put_user(crtc->base.id, crtc_id + copied)) {
+				ret = -EFAULT;
+				goto out;
 			}
-		} else {
-			for (i = 0; i < mode_group->num_crtcs; i++) {
-				if (put_user(mode_group->id_list[i],
-					     crtc_id + copied)) {
-					ret = -EFAULT;
-					goto out;
-				}
-				copied++;
-			}
+			copied++;
 		}
 	}
 	card_res->count_crtcs = crtc_count;
···
 	if (card_res->count_encoders >= encoder_count) {
 		copied = 0;
 		encoder_id = (uint32_t __user *)(unsigned long)card_res->encoder_id_ptr;
-		if (!mode_group) {
-			list_for_each_entry(encoder,
-					    &dev->mode_config.encoder_list,
-					    head) {
-				DRM_DEBUG_KMS("[ENCODER:%d:%s]\n", encoder->base.id,
-						encoder->name);
-				if (put_user(encoder->base.id, encoder_id +
-					     copied)) {
-					ret = -EFAULT;
-					goto out;
-				}
-				copied++;
+		drm_for_each_encoder(encoder, dev) {
+			DRM_DEBUG_KMS("[ENCODER:%d:%s]\n", encoder->base.id,
+					encoder->name);
+			if (put_user(encoder->base.id, encoder_id +
+				     copied)) {
+				ret = -EFAULT;
+				goto out;
 			}
-		} else {
-			for (i = mode_group->num_crtcs; i < mode_group->num_crtcs + mode_group->num_encoders; i++) {
-				if (put_user(mode_group->id_list[i],
-					     encoder_id + copied)) {
-					ret = -EFAULT;
-					goto out;
-				}
-				copied++;
-			}
-
+			copied++;
 		}
 	}
 	card_res->count_encoders = encoder_count;
···
 	if (card_res->count_connectors >= connector_count) {
 		copied = 0;
 		connector_id = (uint32_t __user *)(unsigned long)card_res->connector_id_ptr;
-		if (!mode_group) {
-			list_for_each_entry(connector,
-					    &dev->mode_config.connector_list,
-					    head) {
-				DRM_DEBUG_KMS("[CONNECTOR:%d:%s]\n",
-					connector->base.id,
-					connector->name);
-				if (put_user(connector->base.id,
-					     connector_id + copied)) {
-					ret = -EFAULT;
-					goto out;
-				}
-				copied++;
+		drm_for_each_connector(connector, dev) {
+			DRM_DEBUG_KMS("[CONNECTOR:%d:%s]\n",
+				connector->base.id,
+				connector->name);
+			if (put_user(connector->base.id,
+				     connector_id + copied)) {
+				ret = -EFAULT;
+				goto out;
 			}
-		} else {
-			int start = mode_group->num_crtcs +
-				mode_group->num_encoders;
-			for (i = start; i < start + mode_group->num_connectors; i++) {
-				if (put_user(mode_group->id_list[i],
-					     connector_id + copied)) {
-					ret = -EFAULT;
-					goto out;
-				}
-				copied++;
-			}
+			copied++;
 		}
 	}
 	card_res->count_connectors = connector_count;
···
 
 	/* For atomic drivers only state objects are synchronously updated and
 	 * protected by modeset locks, so check those first. */
-	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
+	drm_for_each_connector(connector, dev) {
 		if (!connector->state)
 			continue;
 
···
 		plane_ptr = (uint32_t __user *)(unsigned long)plane_resp->plane_id_ptr;
 
 		/* Plane lists are invariant, no locking needed. */
-		list_for_each_entry(plane, &config->plane_list, head) {
+		drm_for_each_plane(plane, dev) {
 			/*
 			 * Unless userspace set the 'universal planes'
 			 * capability bit, only advertise overlays.
···
 	 * connectors from it), hence we need to refcount the fbs across all
 	 * crtcs. Atomic modeset will have saner semantics ...
 	 */
-	list_for_each_entry(tmp, &crtc->dev->mode_config.crtc_list, head)
+	drm_for_each_crtc(tmp, crtc->dev)
 		tmp->primary->old_fb = tmp->primary->fb;
 
 	fb = set->fb;
···
 		crtc->primary->fb = fb;
 	}
 
-	list_for_each_entry(tmp, &crtc->dev->mode_config.crtc_list, head) {
+	drm_for_each_crtc(tmp, crtc->dev) {
 		if (tmp->primary->fb)
 			drm_framebuffer_reference(tmp->primary->fb);
 		if (tmp->primary->old_fb)
···
 	struct drm_encoder *encoder;
 	struct drm_connector *connector;
 
-	list_for_each_entry(plane, &dev->mode_config.plane_list, head)
+	drm_for_each_plane(plane, dev)
 		if (plane->funcs->reset)
 			plane->funcs->reset(plane);
 
-	list_for_each_entry(crtc, &dev->mode_config.crtc_list, head)
+	drm_for_each_crtc(crtc, dev)
 		if (crtc->funcs->reset)
 			crtc->funcs->reset(crtc);
 
-	list_for_each_entry(encoder, &dev->mode_config.encoder_list, head)
+	drm_for_each_encoder(encoder, dev)
 		if (encoder->funcs->reset)
 			encoder->funcs->reset(encoder);
 
-	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
+	drm_for_each_connector(connector, dev) {
 		connector->status = connector_status_unknown;
 
 		if (connector->funcs->reset)

drivers/gpu/drm/drm_crtc_helper.c

···
 		WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
 	}
 
-	list_for_each_entry(connector, &dev->mode_config.connector_list, head)
+	drm_for_each_connector(connector, dev)
 		if (connector->encoder == encoder)
 			return true;
 	return false;
···
 	if (!oops_in_progress)
 		WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
 
-	list_for_each_entry(encoder, &dev->mode_config.encoder_list, head)
+	drm_for_each_encoder(encoder, dev)
 		if (encoder->crtc == crtc && drm_helper_encoder_in_use(encoder))
 			return true;
 	return false;
···
 
 	drm_warn_on_modeset_not_all_locked(dev);
 
-	list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
+	drm_for_each_encoder(encoder, dev) {
 		if (!drm_helper_encoder_in_use(encoder)) {
 			drm_encoder_disable(encoder);
 			/* disconnect encoder from any connector */
···
 		}
 	}
 
-	list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
+	drm_for_each_crtc(crtc, dev) {
 		const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 		crtc->enabled = drm_helper_crtc_in_use(crtc);
 		if (!crtc->enabled) {
···
 	const struct drm_encoder_helper_funcs *encoder_funcs;
 	struct drm_encoder *encoder;
 
-	list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
+	drm_for_each_encoder(encoder, dev) {
 		encoder_funcs = encoder->helper_private;
 		/* Disable unused encoders */
 		if (encoder->crtc == NULL)
···
 	 * adjust it according to limitations or connector properties, and also
 	 * a chance to reject the mode entirely.
 	 */
-	list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
+	drm_for_each_encoder(encoder, dev) {
 
 		if (encoder->crtc != crtc)
 			continue;
···
 	crtc->hwmode = *adjusted_mode;
 
 	/* Prepare the encoders and CRTCs before setting the mode. */
-	list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
+	drm_for_each_encoder(encoder, dev) {
 
 		if (encoder->crtc != crtc)
 			continue;
···
 	if (!ret)
 	    goto done;
 
-	list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
+	drm_for_each_encoder(encoder, dev) {
 
 		if (encoder->crtc != crtc)
 			continue;
···
 	/* Now enable the clocks, plane, pipe, and connectors that we set up. */
 	crtc_funcs->commit(crtc);
 
-	list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
+	drm_for_each_encoder(encoder, dev) {
 
 		if (encoder->crtc != crtc)
 			continue;
···
 	struct drm_encoder *encoder;
 
 	/* Decouple all encoders and their attached connectors from this crtc */
-	list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
+	drm_for_each_encoder(encoder, dev) {
 		if (encoder->crtc != crtc)
 			continue;
 
-		list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
+		drm_for_each_connector(connector, dev) {
 			if (connector->encoder != encoder)
 				continue;
 
···
 	 * restored, not the drivers personal bookkeeping.
 	 */
 	count = 0;
-	list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
+	drm_for_each_encoder(encoder, dev) {
 		save_encoders[count++] = *encoder;
 	}
 
 	count = 0;
-	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
+	drm_for_each_connector(connector, dev) {
 		save_connectors[count++] = *connector;
 	}
 
···
 
 	/* a) traverse passed in connector list and get encoders for them */
 	count = 0;
-	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
+	drm_for_each_connector(connector, dev) {
 		const struct drm_connector_helper_funcs *connector_funcs =
 			connector->helper_private;
 		new_encoder = connector->encoder;
···
 	}
 
 	count = 0;
-	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
+	drm_for_each_connector(connector, dev) {
 		if (!connector->encoder)
 			continue;
 
···
 fail:
 	/* Restore all previous data. */
 	count = 0;
-	list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
+	drm_for_each_encoder(encoder, dev) {
 		*encoder = save_encoders[count++];
 	}
 
 	count = 0;
-	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
+	drm_for_each_connector(connector, dev) {
 		*connector = save_connectors[count++];
 	}
 
···
 	struct drm_connector *connector;
 	struct drm_device *dev = encoder->dev;
 
-	list_for_each_entry(connector, &dev->mode_config.connector_list, head)
+	drm_for_each_connector(connector, dev)
 		if (connector->encoder == encoder)
 			if (connector->dpms < dpms)
 				dpms = connector->dpms;
···
 	struct drm_connector *connector;
 	struct drm_device *dev = crtc->dev;
 
-	list_for_each_entry(connector, &dev->mode_config.connector_list, head)
+	drm_for_each_connector(connector, dev)
 		if (connector->encoder && connector->encoder->crtc == crtc)
 			if (connector->dpms < dpms)
 				dpms = connector->dpms;
···
 	bool ret;
 
 	drm_modeset_lock_all(dev);
-	list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
+	drm_for_each_crtc(crtc, dev) {
 
 		if (!crtc->enabled)
 			continue;
···
 
 		/* Turn off outputs that were already powered off */
 		if (drm_helper_choose_crtc_dpms(crtc)) {
-			list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
+			drm_for_each_encoder(encoder, dev) {
 
 				if(encoder->crtc != crtc)
 					continue;

drivers/gpu/drm/drm_drv.c

···
 	if (!minor)
 		return;
 
-	drm_mode_group_destroy(&minor->mode_group);
 	put_device(minor->kdev);
 
 	spin_lock_irqsave(&drm_minor_lock, flags);
···
 			goto err_minors;
 	}
 
-	/* setup grouping for legacy outputs */
-	if (drm_core_check_feature(dev, DRIVER_MODESET)) {
-		ret = drm_mode_group_init_legacy_group(dev,
-				&dev->primary->mode_group);
-		if (ret)
-			goto err_unload;
-	}
-
 	ret = 0;
 	goto out_unlock;
 
-err_unload:
-	if (dev->driver->unload)
-		dev->driver->unload(dev);
 err_minors:
 	drm_minor_unregister(dev, DRM_MINOR_LEGACY);
 	drm_minor_unregister(dev, DRM_MINOR_RENDER);

drivers/gpu/drm/drm_edid.c

···
 	WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
 	WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
 
-	list_for_each_entry(connector, &dev->mode_config.connector_list, head)
+	drm_for_each_connector(connector, dev)
 		if (connector->encoder == encoder && connector->eld[0])
 			return connector;
 

drivers/gpu/drm/drm_fb_cma_helper.c

···
 	struct drm_info_node *node = (struct drm_info_node *) m->private;
 	struct drm_device *dev = node->minor->dev;
 	struct drm_framebuffer *fb;
-	int ret;
 
-	ret = mutex_lock_interruptible(&dev->mode_config.mutex);
-	if (ret)
-		return ret;
-
-	ret = mutex_lock_interruptible(&dev->struct_mutex);
-	if (ret) {
-		mutex_unlock(&dev->mode_config.mutex);
-		return ret;
-	}
-
-	list_for_each_entry(fb, &dev->mode_config.fb_list, head)
+	mutex_lock(&dev->mode_config.fb_lock);
+	drm_for_each_fb(fb, dev)
 		drm_fb_cma_describe(fb, m);
-
-	mutex_unlock(&dev->struct_mutex);
-	mutex_unlock(&dev->mode_config.mutex);
+	mutex_unlock(&dev->mode_config.fb_lock);
 
 	return 0;
 }

drivers/gpu/drm/drm_fb_helper.c

···
  * connectors to the fbdev, e.g. if some are reserved for special purposes or
  * not adequate to be used for the fbcon.
  *
- * Since this is part of the initial setup before the fbdev is published, no
- * locking is required.
+ * This function is protected against concurrent connector hotadds/removals
+ * using drm_fb_helper_add_one_connector() and
+ * drm_fb_helper_remove_one_connector().
  */
 int drm_fb_helper_single_add_all_connectors(struct drm_fb_helper *fb_helper)
 {
···
 	struct drm_connector *connector;
 	int i;
 
-	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
+	mutex_lock(&dev->mode_config.mutex);
+	drm_for_each_connector(connector, dev) {
 		struct drm_fb_helper_connector *fb_helper_connector;
 
 		fb_helper_connector = kzalloc(sizeof(struct drm_fb_helper_connector), GFP_KERNEL);
···
 		fb_helper_connector->connector = connector;
 		fb_helper->connector_info[fb_helper->connector_count++] = fb_helper_connector;
 	}
+	mutex_unlock(&dev->mode_config.mutex);
 	return 0;
 fail:
 	for (i = 0; i < fb_helper->connector_count; i++) {
···
 		fb_helper->connector_info[i] = NULL;
 	}
 	fb_helper->connector_count = 0;
+	mutex_unlock(&dev->mode_config.mutex);
+
 	return -ENOMEM;
 }
 EXPORT_SYMBOL(drm_fb_helper_single_add_all_connectors);
···
 	struct drm_device *dev = crtc->dev;
 	struct drm_crtc *c;
 
-	list_for_each_entry(c, &dev->mode_config.crtc_list, head) {
+	drm_for_each_crtc(c, dev) {
 		if (crtc->base.id == c->base.id)
 			return c->primary->fb;
 	}
···
 
 	drm_warn_on_modeset_not_all_locked(dev);
 
-	list_for_each_entry(plane, &dev->mode_config.plane_list, head) {
+	drm_for_each_plane(plane, dev) {
 		if (plane->type != DRM_PLANE_TYPE_PRIMARY)
 			drm_plane_force_disable(plane);
 
···
 	if (dev->primary->master)
 		return false;
 
-	list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
+	drm_for_each_crtc(crtc, dev) {
 		if (crtc->primary->fb)
 			crtcs_bound++;
 		if (crtc->primary->fb == fb_helper->fb)
···
 	}
 
 	i = 0;
-	list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
+	drm_for_each_crtc(crtc, dev) {
 		fb_helper->crtc_info[i].mode_set.crtc = crtc;
 		i++;
 	}

drivers/gpu/drm/drm_gem_cma_helper.c

···
 			  struct seq_file *m)
 {
 	struct drm_gem_object *obj = &cma_obj->base;
-	struct drm_device *dev = obj->dev;
 	uint64_t off;
-
-	WARN_ON(!mutex_is_locked(&dev->struct_mutex));
 
 	off = drm_vma_node_start(&obj->vma_node);
 

drivers/gpu/drm/drm_modeset_lock.c

···
 	if (oops_in_progress)
 		return;
 
-	list_for_each_entry(crtc, &dev->mode_config.crtc_list, head)
+	drm_for_each_crtc(crtc, dev)
 		WARN_ON(!drm_modeset_is_locked(&crtc->mutex));
 
 	WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
···
 int drm_modeset_lock_all_crtcs(struct drm_device *dev,
 		struct drm_modeset_acquire_ctx *ctx)
 {
-	struct drm_mode_config *config = &dev->mode_config;
 	struct drm_crtc *crtc;
 	struct drm_plane *plane;
 	int ret = 0;
 
-	list_for_each_entry(crtc, &config->crtc_list, head) {
+	drm_for_each_crtc(crtc, dev) {
 		ret = drm_modeset_lock(&crtc->mutex, ctx);
 		if (ret)
 			return ret;
 	}
 
-	list_for_each_entry(plane, &config->plane_list, head) {
+	drm_for_each_plane(plane, dev) {
 		ret = drm_modeset_lock(&plane->mutex, ctx);
 		if (ret)
 			return ret;

drivers/gpu/drm/drm_of.c

···
 	unsigned int index = 0;
 	struct drm_crtc *tmp;
 
-	list_for_each_entry(tmp, &dev->mode_config.crtc_list, head) {
+	drm_for_each_crtc(tmp, dev) {
 		if (tmp->port == port)
 			return 1 << index;
 

drivers/gpu/drm/drm_plane_helper.c

···
 	 */
 	WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
 
-	list_for_each_entry(connector, &dev->mode_config.connector_list, head)
+	drm_for_each_connector(connector, dev) {
 		if (connector->encoder && connector->encoder->crtc == crtc) {
 			if (connector_list != NULL && count < num_connectors)
 				*(connector_list++) = connector;
 
 			count++;
 		}
+	}
 
 	return count;
 }

drivers/gpu/drm/drm_probe_helper.c

···
 	return 1;
 }
 
+#define DRM_OUTPUT_POLL_PERIOD (10*HZ)
+static void __drm_kms_helper_poll_enable(struct drm_device *dev)
+{
+	bool poll = false;
+	struct drm_connector *connector;
+
+	WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
+
+	if (!dev->mode_config.poll_enabled || !drm_kms_helper_poll)
+		return;
+
+	drm_for_each_connector(connector, dev) {
+		if (connector->polled & (DRM_CONNECTOR_POLL_CONNECT |
+					 DRM_CONNECTOR_POLL_DISCONNECT))
+			poll = true;
+	}
+
+	if (poll)
+		schedule_delayed_work(&dev->mode_config.output_poll_work, DRM_OUTPUT_POLL_PERIOD);
+}
+
 static int drm_helper_probe_single_connector_modes_merge_bits(struct drm_connector *connector,
 							      uint32_t maxX, uint32_t maxY, bool merge_type_bits)
 {
···
 
 	/* Re-enable polling in case the global poll config changed. */
 	if (drm_kms_helper_poll != dev->mode_config.poll_running)
-		drm_kms_helper_poll_enable(dev);
+		__drm_kms_helper_poll_enable(dev);
 
 	dev->mode_config.poll_running = drm_kms_helper_poll;
 
···
 }
 EXPORT_SYMBOL(drm_kms_helper_hotplug_event);
 
-#define DRM_OUTPUT_POLL_PERIOD (10*HZ)
 static void output_poll_execute(struct work_struct *work)
 {
 	struct delayed_work *delayed_work = to_delayed_work(work);
···
 		goto out;
 
 	mutex_lock(&dev->mode_config.mutex);
-	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
+	drm_for_each_connector(connector, dev) {
 
 		/* Ignore forced connectors. */
 		if (connector->force)
···
  */
 void drm_kms_helper_poll_enable(struct drm_device *dev)
 {
-	bool poll = false;
-	struct drm_connector *connector;
-
-	if (!dev->mode_config.poll_enabled || !drm_kms_helper_poll)
-		return;
-
-	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
-		if (connector->polled & (DRM_CONNECTOR_POLL_CONNECT |
-					 DRM_CONNECTOR_POLL_DISCONNECT))
-			poll = true;
-	}
-
-	if (poll)
-		schedule_delayed_work(&dev->mode_config.output_poll_work, DRM_OUTPUT_POLL_PERIOD);
+	mutex_lock(&dev->mode_config.mutex);
+	__drm_kms_helper_poll_enable(dev);
+	mutex_unlock(&dev->mode_config.mutex);
 }
 EXPORT_SYMBOL(drm_kms_helper_poll_enable);
 
···
 		return false;
 
 	mutex_lock(&dev->mode_config.mutex);
-	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
+	drm_for_each_connector(connector, dev) {
 
 		/* Only handle HPD capable connectors. */
 		if (!(connector->polled & DRM_CONNECTOR_POLL_HPD))

drivers/gpu/drm/i915/i915_debugfs.c

···
 	struct drm_device *dev = node->minor->dev;
 	struct intel_fbdev *ifbdev = NULL;
 	struct intel_framebuffer *fb;
+	struct drm_framebuffer *drm_fb;
 
 #ifdef CONFIG_DRM_I915_FBDEV
 	struct drm_i915_private *dev_priv = dev->dev_private;
···
 #endif
 
 	mutex_lock(&dev->mode_config.fb_lock);
-	list_for_each_entry(fb, &dev->mode_config.fb_list, base.head) {
+	drm_for_each_fb(drm_fb, dev) {
+		fb = to_intel_framebuffer(drm_fb);
 		if (ifbdev && &fb->base == ifbdev->helper.fb)
 			continue;
 

drivers/gpu/drm/i915/intel_dp_mst.c

···
 	drm_object_attach_property(&connector->base, dev->mode_config.tile_property, 0);
 
 	drm_mode_connector_set_path_property(connector, pathprop);
-	drm_reinit_primary_mode_group(dev);
-	mutex_lock(&dev->mode_config.mutex);
+	drm_modeset_lock_all(dev);
 	intel_connector_add_to_fbdev(intel_connector);
-	mutex_unlock(&dev->mode_config.mutex);
+	drm_modeset_unlock_all(dev);
 	drm_connector_register(&intel_connector->base);
 	return connector;
 }
···
 	struct intel_connector *intel_connector = to_intel_connector(connector);
 	struct drm_device *dev = connector->dev;
 	/* need to nuke the connector */
-	mutex_lock(&dev->mode_config.mutex);
+	drm_modeset_lock_all(dev);
 	intel_connector_dpms(connector, DRM_MODE_DPMS_OFF);
-	mutex_unlock(&dev->mode_config.mutex);
+	drm_modeset_unlock_all(dev);
 
 	intel_connector->unregister(intel_connector);
 
-	mutex_lock(&dev->mode_config.mutex);
+	drm_modeset_lock_all(dev);
 	intel_connector_remove_from_fbdev(intel_connector);
 	drm_connector_cleanup(connector);
-	mutex_unlock(&dev->mode_config.mutex);
-
-	drm_reinit_primary_mode_group(dev);
+	drm_modeset_unlock_all(dev);
 
 	kfree(intel_connector);
 	DRM_DEBUG_KMS("\n");

drivers/gpu/drm/i915/intel_pm.c

···
 	p->pri.horiz_pixels = intel_crtc->config->pipe_src_w;
 	p->cur.horiz_pixels = intel_crtc->base.cursor->state->crtc_w;
 
-	drm_for_each_legacy_plane(plane, &dev->mode_config.plane_list) {
+	drm_for_each_legacy_plane(plane, dev) {
 		struct intel_plane *intel_plane = to_intel_plane(plane);
 
 		if (intel_plane->pipe == pipe) {

drivers/gpu/drm/radeon/radeon_dp_mst.c

···
 
 	drm_object_attach_property(&connector->base, dev->mode_config.path_property, 0);
 	drm_mode_connector_set_path_property(connector, pathprop);
-	drm_reinit_primary_mode_group(dev);
 
-	mutex_lock(&dev->mode_config.mutex);
+	drm_modeset_lock_all(dev);
 	radeon_fb_add_connector(rdev, connector);
-	mutex_unlock(&dev->mode_config.mutex);
+	drm_modeset_unlock_all(dev);
 
 	drm_connector_register(connector);
 	return connector;
···
 
 	drm_connector_unregister(connector);
 	/* need to nuke the connector */
-	mutex_lock(&dev->mode_config.mutex);
+	drm_modeset_lock_all(dev);
 	/* dpms off */
 	radeon_fb_remove_connector(rdev, connector);
 
 	drm_connector_cleanup(connector);
-	mutex_unlock(&dev->mode_config.mutex);
-	drm_reinit_primary_mode_group(dev);
-
+	drm_modeset_unlock_all(dev);
 
 	kfree(connector);
 	DRM_DEBUG_KMS("\n");

drivers/gpu/drm/shmobile/shmob_drm_crtc.c

···
 	lcdc_write(sdev, LDDDSR, value);
 
 	/* Setup planes. */
-	drm_for_each_legacy_plane(plane, &dev->mode_config.plane_list) {
+	drm_for_each_legacy_plane(plane, dev) {
 		if (plane->crtc == crtc)
 			shmob_drm_plane_setup(plane);
 	}

include/drm/drmP.h

···
 
 	/* currently active master for this node. Protected by master_mutex */
 	struct drm_master *master;
-	struct drm_mode_group mode_group;
 };
 
 

include/drm/drm_crtc.h

···
 };
 
 /**
- * struct drm_mode_group - group of mode setting resources for potential sub-grouping
- * @num_crtcs: CRTC count
- * @num_encoders: encoder count
- * @num_connectors: connector count
- * @num_bridges: bridge count
- * @id_list: list of KMS object IDs in this group
- *
- * Currently this simply tracks the global mode setting state.  But in the
- * future it could allow groups of objects to be set aside into independent
- * control groups for use by different user level processes (e.g. two X servers
- * running simultaneously on different heads, each with their own mode
- * configuration and freedom of mode setting).
- */
-struct drm_mode_group {
-	uint32_t num_crtcs;
-	uint32_t num_encoders;
-	uint32_t num_connectors;
-
-	/* list of object IDs for this group */
-	uint32_t *id_list;
-};
-
-/**
  * struct drm_mode_config - Mode configuration control structure
  * @mutex: mutex protecting KMS related lists and structures
  * @connection_mutex: ww mutex protecting connector state and routing
···
 extern void drm_fb_release(struct drm_file *file_priv);
 extern void drm_property_destroy_user_blobs(struct drm_device *dev,
                                             struct drm_file *file_priv);
-extern int drm_mode_group_init_legacy_group(struct drm_device *dev, struct drm_mode_group *group);
-extern void drm_mode_group_destroy(struct drm_mode_group *group);
-extern void drm_reinit_primary_mode_group(struct drm_device *dev);
 extern bool drm_probe_ddc(struct i2c_adapter *adapter);
 extern struct edid *drm_get_edid(struct drm_connector *connector,
 				 struct i2c_adapter *adapter);
···
 }
 
 /* Plane list iterator for legacy (overlay only) planes. */
-#define drm_for_each_legacy_plane(plane, planelist) \
-	list_for_each_entry(plane, planelist, head) \
+#define drm_for_each_legacy_plane(plane, dev) \
+	list_for_each_entry(plane, &(dev)->mode_config.plane_list, head) \
 		if (plane->type == DRM_PLANE_TYPE_OVERLAY)
+
+#define drm_for_each_plane(plane, dev) \
+	list_for_each_entry(plane, &(dev)->mode_config.plane_list, head)
+
+#define drm_for_each_crtc(crtc, dev) \
+	list_for_each_entry(crtc, &(dev)->mode_config.crtc_list, head)
+
+static inline void
+assert_drm_connector_list_read_locked(struct drm_mode_config *mode_config)
+{
+	/*
+	 * The connector hotadd/remove code currently grabs both locks when
+	 * updating lists. Hence readers need only hold either of them to be
+	 * safe and the check amounts to
+	 *
+	 * WARN_ON(not_holding(A) && not_holding(B)).
+	 */
+	WARN_ON(!mutex_is_locked(&mode_config->mutex) &&
+		!drm_modeset_is_locked(&mode_config->connection_mutex));
+}
+
+#define drm_for_each_connector(connector, dev) \
+	for (assert_drm_connector_list_read_locked(&(dev)->mode_config),	\
+	     connector = list_first_entry(&(dev)->mode_config.connector_list,	\
+					  struct drm_connector, head);		\
+	     &connector->head != (&(dev)->mode_config.connector_list);		\
+	     connector = list_next_entry(connector, head))
+
+#define drm_for_each_encoder(encoder, dev) \
+	list_for_each_entry(encoder, &(dev)->mode_config.encoder_list, head)
+
+#define drm_for_each_fb(fb, dev) \
+	for (WARN_ON(!mutex_is_locked(&(dev)->mode_config.fb_lock)),		\
+	     fb = list_first_entry(&(dev)->mode_config.fb_list,	\
+					  struct drm_framebuffer, head);	\
+	     &fb->head != (&(dev)->mode_config.fb_list);			\
+	     fb = list_next_entry(fb, head))
 
 #endif /* __DRM_CRTC_H__ */