1 files changed, 62 insertions, 88 deletions

diff --git a/drivers/gpu/drm/drm_mode_config.c b/drivers/gpu/drm/drm_mode_config.c
index 2735a5847ffa..884cc4d26fb5 100644
--- a/drivers/gpu/drm/drm_mode_config.c
+++ b/drivers/gpu/drm/drm_mode_config.c
@@ -20,6 +20,7 @@
  * OF THIS SOFTWARE.
  */
 
+#include <drm/drm_encoder.h>
 #include <drm/drm_mode_config.h>
 #include <drm/drmP.h>
 
@@ -84,113 +85,74 @@ int drm_mode_getresources(struct drm_device *dev, void *data,
 			  struct drm_file *file_priv)
 {
 	struct drm_mode_card_res *card_res = data;
-	struct list_head *lh;
 	struct drm_framebuffer *fb;
 	struct drm_connector *connector;
 	struct drm_crtc *crtc;
 	struct drm_encoder *encoder;
-	int ret = 0;
-	int connector_count = 0;
-	int crtc_count = 0;
-	int fb_count = 0;
-	int encoder_count = 0;
-	int copied = 0;
+	int count, ret = 0;
 	uint32_t __user *fb_id;
 	uint32_t __user *crtc_id;
 	uint32_t __user *connector_id;
 	uint32_t __user *encoder_id;
+	struct drm_connector_list_iter conn_iter;
 
 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
 		return -EINVAL;
 
 
 	mutex_lock(&file_priv->fbs_lock);
-	/*
-	 * For the non-control nodes we need to limit the list of resources
-	 * by IDs in the group list for this node
-	 */
-	list_for_each(lh, &file_priv->fbs)
-		fb_count++;
-
-	/* handle this in 4 parts */
-	/* FBs */
-	if (card_res->count_fbs >= fb_count) {
-		copied = 0;
-		fb_id = (uint32_t __user *)(unsigned long)card_res->fb_id_ptr;
-		list_for_each_entry(fb, &file_priv->fbs, filp_head) {
-			if (put_user(fb->base.id, fb_id + copied)) {
-				mutex_unlock(&file_priv->fbs_lock);
-				return -EFAULT;
-			}
-			copied++;
+	count = 0;
+	fb_id = u64_to_user_ptr(card_res->fb_id_ptr);
+	list_for_each_entry(fb, &file_priv->fbs, filp_head) {
+		if (count < card_res->count_fbs &&
+		    put_user(fb->base.id, fb_id + count)) {
+			mutex_unlock(&file_priv->fbs_lock);
+			return -EFAULT;
 		}
+		count++;
 	}
-	card_res->count_fbs = fb_count;
+	card_res->count_fbs = count;
 	mutex_unlock(&file_priv->fbs_lock);
 
-	/* 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);
-	drm_for_each_crtc(crtc, dev)
-		crtc_count++;
-
-	drm_for_each_connector(connector, dev)
-		connector_count++;
-
-	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;
 	card_res->max_width = dev->mode_config.max_width;
 	card_res->min_width = dev->mode_config.min_width;
 
-	/* CRTCs */
-	if (card_res->count_crtcs >= crtc_count) {
-		copied = 0;
-		crtc_id = (uint32_t __user *)(unsigned long)card_res->crtc_id_ptr;
-		drm_for_each_crtc(crtc, dev) {
-			if (put_user(crtc->base.id, crtc_id + copied)) {
-				ret = -EFAULT;
-				goto out;
-			}
-			copied++;
-		}
+	count = 0;
+	crtc_id = u64_to_user_ptr(card_res->crtc_id_ptr);
+	drm_for_each_crtc(crtc, dev) {
+		if (count < card_res->count_crtcs &&
+		    put_user(crtc->base.id, crtc_id + count))
+			return -EFAULT;
+		count++;
 	}
-	card_res->count_crtcs = crtc_count;
-
-	/* Encoders */
-	if (card_res->count_encoders >= encoder_count) {
-		copied = 0;
-		encoder_id = (uint32_t __user *)(unsigned long)card_res->encoder_id_ptr;
-		drm_for_each_encoder(encoder, dev) {
-			if (put_user(encoder->base.id, encoder_id +
-				     copied)) {
-				ret = -EFAULT;
-				goto out;
-			}
-			copied++;
-		}
+	card_res->count_crtcs = count;
+
+	count = 0;
+	encoder_id = u64_to_user_ptr(card_res->encoder_id_ptr);
+	drm_for_each_encoder(encoder, dev) {
+		if (count < card_res->count_encoders &&
+		    put_user(encoder->base.id, encoder_id + count))
+			return -EFAULT;
+		count++;
 	}
-	card_res->count_encoders = encoder_count;
-
-	/* Connectors */
-	if (card_res->count_connectors >= connector_count) {
-		copied = 0;
-		connector_id = (uint32_t __user *)(unsigned long)card_res->connector_id_ptr;
-		drm_for_each_connector(connector, dev) {
-			if (put_user(connector->base.id,
-				     connector_id + copied)) {
-				ret = -EFAULT;
-				goto out;
-			}
-			copied++;
+	card_res->count_encoders = count;
+
+	drm_connector_list_iter_get(dev, &conn_iter);
+	count = 0;
+	connector_id = u64_to_user_ptr(card_res->connector_id_ptr);
+	drm_for_each_connector_iter(connector, &conn_iter) {
+		if (count < card_res->count_connectors &&
+		    put_user(connector->base.id, connector_id + count)) {
+			drm_connector_list_iter_put(&conn_iter);
+			return -EFAULT;
 		}
+		count++;
 	}
-	card_res->count_connectors = connector_count;
+	card_res->count_connectors = count;
+	drm_connector_list_iter_put(&conn_iter);
 
-out:
-	mutex_unlock(&dev->mode_config.mutex);
 	return ret;
 }
 
@@ -208,6 +170,7 @@ void drm_mode_config_reset(struct drm_device *dev)
 	struct drm_plane *plane;
 	struct drm_encoder *encoder;
 	struct drm_connector *connector;
+	struct drm_connector_list_iter conn_iter;
 
 	drm_for_each_plane(plane, dev)
 		if (plane->funcs->reset)
@@ -221,11 +184,11 @@ void drm_mode_config_reset(struct drm_device *dev)
 		if (encoder->funcs->reset)
 			encoder->funcs->reset(encoder);
 
-	mutex_lock(&dev->mode_config.mutex);
-	drm_for_each_connector(connector, dev)
+	drm_connector_list_iter_get(dev, &conn_iter);
+	drm_for_each_connector_iter(connector, &conn_iter)
 		if (connector->funcs->reset)
 			connector->funcs->reset(connector);
-	mutex_unlock(&dev->mode_config.mutex);
+	drm_connector_list_iter_put(&conn_iter);
 }
 EXPORT_SYMBOL(drm_mode_config_reset);
 
@@ -406,10 +369,9 @@ void drm_mode_config_init(struct drm_device *dev)
 	idr_init(&dev->mode_config.crtc_idr);
 	idr_init(&dev->mode_config.tile_idr);
 	ida_init(&dev->mode_config.connector_ida);
+	spin_lock_init(&dev->mode_config.connector_list_lock);
 
-	drm_modeset_lock_all(dev);
 	drm_mode_create_standard_properties(dev);
-	drm_modeset_unlock_all(dev);
 
 	/* Just to be sure */
 	dev->mode_config.num_fb = 0;
@@ -436,7 +398,8 @@ EXPORT_SYMBOL(drm_mode_config_init);
  */
 void drm_mode_config_cleanup(struct drm_device *dev)
 {
-	struct drm_connector *connector, *ot;
+	struct drm_connector *connector;
+	struct drm_connector_list_iter conn_iter;
 	struct drm_crtc *crtc, *ct;
 	struct drm_encoder *encoder, *enct;
 	struct drm_framebuffer *fb, *fbt;
@@ -449,9 +412,20 @@ void drm_mode_config_cleanup(struct drm_device *dev)
 		encoder->funcs->destroy(encoder);
 	}
 
-	list_for_each_entry_safe(connector, ot,
-				 &dev->mode_config.connector_list, head) {
-		connector->funcs->destroy(connector);
+	drm_connector_list_iter_get(dev, &conn_iter);
+	drm_for_each_connector_iter(connector, &conn_iter) {
+		/* drm_connector_list_iter holds an full reference to the
+		 * current connector itself, which means it is inherently safe
+		 * against unreferencing the current connector - but not against
+		 * deleting it right away. */
+		drm_connector_unreference(connector);
+	}
+	drm_connector_list_iter_put(&conn_iter);
+	if (WARN_ON(!list_empty(&dev->mode_config.connector_list))) {
+		drm_connector_list_iter_get(dev, &conn_iter);
+		drm_for_each_connector_iter(connector, &conn_iter)
+			DRM_ERROR("connector %s leaked!\n", connector->name);
+		drm_connector_list_iter_put(&conn_iter);
 	}
 
 	list_for_each_entry_safe(property, pt, &dev->mode_config.property_list,