drm: Convert all helpers to drm_connector_list_iter

Mostly nothing special (except making sure that really all error paths
and friends call iter_put).

v2: Don't forget the raw connector_list walking in
drm_helper_move_panel_connectors_to_head. That one unfortunately can't
be converted to the iterator helpers, but since it's just some list
splicing best to just wrap the entire thing up in one critical
section.

v3: Bail out after iter_put (Harry).

Cc: Harry Wentland <harry.wentland@amd.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161215155843.13408-1-daniel.vetter@ffwll.ch

6 files changed, 92 insertions, 33 deletions

diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index 23767df72615..e2e15a9903a9 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -94,9 +94,10 @@ static int handle_conflicting_encoders(struct drm_atomic_state *state,
 {
 	struct drm_connector_state *conn_state;
 	struct drm_connector *connector;
+	struct drm_connector_list_iter conn_iter;
 	struct drm_encoder *encoder;
 	unsigned encoder_mask = 0;
-	int i, ret;
+	int i, ret = 0;
 
 	/*
 	 * First loop, find all newly assigned encoders from the connectors
@@ -144,7 +145,8 @@ static int handle_conflicting_encoders(struct drm_atomic_state *state,
 	 * and the crtc is disabled if no encoder is left. This preserves
 	 * compatibility with the legacy set_config behavior.
 	 */
-	drm_for_each_connector(connector, state->dev) {
+	drm_connector_list_iter_get(state->dev, &conn_iter);
+	drm_for_each_connector_iter(connector, &conn_iter) {
 		struct drm_crtc_state *crtc_state;
 
 		if (drm_atomic_get_existing_connector_state(state, connector))
@@ -160,12 +162,15 @@ static int handle_conflicting_encoders(struct drm_atomic_state *state,
 					 connector->state->crtc->base.id,
 					 connector->state->crtc->name,
 					 connector->base.id, connector->name);
-			return -EINVAL;
+			ret = -EINVAL;
+			goto out;
 		}
 
 		conn_state = drm_atomic_get_connector_state(state, connector);
-		if (IS_ERR(conn_state))
-			return PTR_ERR(conn_state);
+		if (IS_ERR(conn_state)) {
+			ret = PTR_ERR(conn_state);
+			goto out;
+		}
 
 		DRM_DEBUG_ATOMIC("[ENCODER:%d:%s] in use on [CRTC:%d:%s], disabling [CONNECTOR:%d:%s]\n",
 				 encoder->base.id, encoder->name,
@@ -176,19 +181,21 @@ static int handle_conflicting_encoders(struct drm_atomic_state *state,
 
 		ret = drm_atomic_set_crtc_for_connector(conn_state, NULL);
 		if (ret)
-			return ret;
+			goto out;
 
 		if (!crtc_state->connector_mask) {
 			ret = drm_atomic_set_mode_prop_for_crtc(crtc_state,
 								NULL);
 			if (ret < 0)
-				return ret;
+				goto out;
 
 			crtc_state->active = false;
 		}
 	}
+out:
+	drm_connector_list_iter_put(&conn_iter);
 
-	return 0;
+	return ret;
 }
 
 static void
@@ -2442,6 +2449,7 @@ int drm_atomic_helper_disable_all(struct drm_device *dev,
 {
 	struct drm_atomic_state *state;
 	struct drm_connector *conn;
+	struct drm_connector_list_iter conn_iter;
 	int err;
 
 	state = drm_atomic_state_alloc(dev);
@@ -2450,7 +2458,8 @@ int drm_atomic_helper_disable_all(struct drm_device *dev,
 
 	state->acquire_ctx = ctx;
 
-	drm_for_each_connector(conn, dev) {
+	drm_connector_list_iter_get(dev, &conn_iter);
+	drm_for_each_connector_iter(conn, &conn_iter) {
 		struct drm_crtc *crtc = conn->state->crtc;
 		struct drm_crtc_state *crtc_state;
 
@@ -2468,6 +2477,7 @@ int drm_atomic_helper_disable_all(struct drm_device *dev,
 
 	err = drm_atomic_commit(state);
 free:
+	drm_connector_list_iter_put(&conn_iter);
 	drm_atomic_state_put(state);
 	return err;
 }
@@ -2840,6 +2850,7 @@ int drm_atomic_helper_connector_dpms(struct drm_connector *connector,
 	struct drm_crtc_state *crtc_state;
 	struct drm_crtc *crtc;
 	struct drm_connector *tmp_connector;
+	struct drm_connector_list_iter conn_iter;
 	int ret;
 	bool active = false;
 	int old_mode = connector->dpms;
@@ -2867,7 +2878,8 @@ retry:
 
 	WARN_ON(!drm_modeset_is_locked(&config->connection_mutex));
 
-	drm_for_each_connector(tmp_connector, connector->dev) {
+	drm_connector_list_iter_get(connector->dev, &conn_iter);
+	drm_for_each_connector_iter(tmp_connector, &conn_iter) {
 		if (tmp_connector->state->crtc != crtc)
 			continue;
 
@@ -2876,6 +2888,7 @@ retry:
 			break;
 		}
 	}
+	drm_connector_list_iter_put(&conn_iter);
 	crtc_state->active = active;
 
 	ret = drm_atomic_commit(state);
@@ -3253,6 +3266,7 @@ drm_atomic_helper_duplicate_state(struct drm_device *dev,
 {
 	struct drm_atomic_state *state;
 	struct drm_connector *conn;
+	struct drm_connector_list_iter conn_iter;
 	struct drm_plane *plane;
 	struct drm_crtc *crtc;
 	int err = 0;
@@ -3283,15 +3297,18 @@ drm_atomic_helper_duplicate_state(struct drm_device *dev,
 		}
 	}
 
-	drm_for_each_connector(conn, dev) {
+	drm_connector_list_iter_get(dev, &conn_iter);
+	drm_for_each_connector_iter(conn, &conn_iter) {
 		struct drm_connector_state *conn_state;
 
 		conn_state = drm_atomic_get_connector_state(state, conn);
 		if (IS_ERR(conn_state)) {
 			err = PTR_ERR(conn_state);
+			drm_connector_list_iter_put(&conn_iter);
 			goto free;
 		}
 	}
+	drm_connector_list_iter_put(&conn_iter);
 
 	/* clear the acquire context so that it isn't accidentally reused */
 	state->acquire_ctx = NULL;
diff --git a/drivers/gpu/drm/drm_crtc_helper.c b/drivers/gpu/drm/drm_crtc_helper.c
index 26061753f3bf..923a17c05e01 100644
--- a/drivers/gpu/drm/drm_crtc_helper.c
+++ b/drivers/gpu/drm/drm_crtc_helper.c
@@ -89,6 +89,7 @@
 bool drm_helper_encoder_in_use(struct drm_encoder *encoder)
 {
 	struct drm_connector *connector;
+	struct drm_connector_list_iter conn_iter;
 	struct drm_device *dev = encoder->dev;
 
 	/*
@@ -100,9 +101,15 @@ bool drm_helper_encoder_in_use(struct drm_encoder *encoder)
 		WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
 	}
 
-	drm_for_each_connector(connector, dev)
-		if (connector->encoder == encoder)
+
+	drm_connector_list_iter_get(dev, &conn_iter);
+	drm_for_each_connector_iter(connector, &conn_iter) {
+		if (connector->encoder == encoder) {
+			drm_connector_list_iter_put(&conn_iter);
 			return true;
+		}
+	}
+	drm_connector_list_iter_put(&conn_iter);
 	return false;
 }
 EXPORT_SYMBOL(drm_helper_encoder_in_use);
@@ -437,10 +444,13 @@ drm_crtc_helper_disable(struct drm_crtc *crtc)
 
 	/* Decouple all encoders and their attached connectors from this crtc */
 	drm_for_each_encoder(encoder, dev) {
+		struct drm_connector_list_iter conn_iter;
+
 		if (encoder->crtc != crtc)
 			continue;
 
-		drm_for_each_connector(connector, dev) {
+		drm_connector_list_iter_get(dev, &conn_iter);
+		drm_for_each_connector_iter(connector, &conn_iter) {
 			if (connector->encoder != encoder)
 				continue;
 
@@ -457,6 +467,7 @@ drm_crtc_helper_disable(struct drm_crtc *crtc)
 			/* we keep a reference while the encoder is bound */
 			drm_connector_unreference(connector);
 		}
+		drm_connector_list_iter_put(&conn_iter);
 	}
 
 	__drm_helper_disable_unused_functions(dev);
@@ -508,6 +519,7 @@ int drm_crtc_helper_set_config(struct drm_mode_set *set)
 	bool mode_changed = false; /* if true do a full mode set */
 	bool fb_changed = false; /* if true and !mode_changed just do a flip */
 	struct drm_connector *connector;
+	struct drm_connector_list_iter conn_iter;
 	int count = 0, ro, fail = 0;
 	const struct drm_crtc_helper_funcs *crtc_funcs;
 	struct drm_mode_set save_set;
@@ -572,9 +584,10 @@ int drm_crtc_helper_set_config(struct drm_mode_set *set)
 	}
 
 	count = 0;
-	drm_for_each_connector(connector, dev) {
+	drm_connector_list_iter_get(dev, &conn_iter);
+	drm_for_each_connector_iter(connector, &conn_iter)
 		save_connector_encoders[count++] = connector->encoder;
-	}
+	drm_connector_list_iter_put(&conn_iter);
 
 	save_set.crtc = set->crtc;
 	save_set.mode = &set->crtc->mode;
@@ -616,7 +629,8 @@ int drm_crtc_helper_set_config(struct drm_mode_set *set)
 
 	/* a) traverse passed in connector list and get encoders for them */
 	count = 0;
-	drm_for_each_connector(connector, dev) {
+	drm_connector_list_iter_get(dev, &conn_iter);
+	drm_for_each_connector_iter(connector, &conn_iter) {
 		const struct drm_connector_helper_funcs *connector_funcs =
 			connector->helper_private;
 		new_encoder = connector->encoder;
@@ -649,6 +663,7 @@ int drm_crtc_helper_set_config(struct drm_mode_set *set)
 			connector->encoder = new_encoder;
 		}
 	}
+	drm_connector_list_iter_put(&conn_iter);
 
 	if (fail) {
 		ret = -EINVAL;
@@ -656,7 +671,8 @@ int drm_crtc_helper_set_config(struct drm_mode_set *set)
 	}
 
 	count = 0;
-	drm_for_each_connector(connector, dev) {
+	drm_connector_list_iter_get(dev, &conn_iter);
+	drm_for_each_connector_iter(connector, &conn_iter) {
 		if (!connector->encoder)
 			continue;
 
@@ -674,6 +690,7 @@ int drm_crtc_helper_set_config(struct drm_mode_set *set)
 		if (new_crtc &&
 		    !drm_encoder_crtc_ok(connector->encoder, new_crtc)) {
 			ret = -EINVAL;
+			drm_connector_list_iter_put(&conn_iter);
 			goto fail;
 		}
 		if (new_crtc != connector->encoder->crtc) {
@@ -690,6 +707,7 @@ int drm_crtc_helper_set_config(struct drm_mode_set *set)
 				      connector->base.id, connector->name);
 		}
 	}
+	drm_connector_list_iter_put(&conn_iter);
 
 	/* mode_set_base is not a required function */
 	if (fb_changed && !crtc_funcs->mode_set_base)
@@ -744,9 +762,10 @@ fail:
 	}
 
 	count = 0;
-	drm_for_each_connector(connector, dev) {
+	drm_connector_list_iter_get(dev, &conn_iter);
+	drm_for_each_connector_iter(connector, &conn_iter)
 		connector->encoder = save_connector_encoders[count++];
-	}
+	drm_connector_list_iter_put(&conn_iter);
 
 	/* after fail drop reference on all unbound connectors in set, let
 	 * bound connectors keep their reference
@@ -773,12 +792,16 @@ static int drm_helper_choose_encoder_dpms(struct drm_encoder *encoder)
 {
 	int dpms = DRM_MODE_DPMS_OFF;
 	struct drm_connector *connector;
+	struct drm_connector_list_iter conn_iter;
 	struct drm_device *dev = encoder->dev;
 
-	drm_for_each_connector(connector, dev)
+	drm_connector_list_iter_get(dev, &conn_iter);
+	drm_for_each_connector_iter(connector, &conn_iter)
 		if (connector->encoder == encoder)
 			if (connector->dpms < dpms)
 				dpms = connector->dpms;
+	drm_connector_list_iter_put(&conn_iter);
+
 	return dpms;
 }
 
@@ -810,12 +833,16 @@ static int drm_helper_choose_crtc_dpms(struct drm_crtc *crtc)
 {
 	int dpms = DRM_MODE_DPMS_OFF;
 	struct drm_connector *connector;
+	struct drm_connector_list_iter conn_iter;
 	struct drm_device *dev = crtc->dev;
 
-	drm_for_each_connector(connector, dev)
+	drm_connector_list_iter_get(dev, &conn_iter);
+	drm_for_each_connector_iter(connector, &conn_iter)
 		if (connector->encoder && connector->encoder->crtc == crtc)
 			if (connector->dpms < dpms)
 				dpms = connector->dpms;
+	drm_connector_list_iter_put(&conn_iter);
+
 	return dpms;
 }
 
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index bee5e4149a1c..145d55fef69e 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -120,20 +120,22 @@ int drm_fb_helper_single_add_all_connectors(struct drm_fb_helper *fb_helper)
 {
 	struct drm_device *dev = fb_helper->dev;
 	struct drm_connector *connector;
-	int i, ret;
+	struct drm_connector_list_iter conn_iter;
+	int i, ret = 0;
 
 	if (!drm_fbdev_emulation)
 		return 0;
 
 	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) {
 		ret = drm_fb_helper_add_one_connector(fb_helper, connector);
 
 		if (ret)
 			goto fail;
 	}
-	mutex_unlock(&dev->mode_config.mutex);
-	return 0;
+	goto out;
+
 fail:
 	drm_fb_helper_for_each_connector(fb_helper, i) {
 		struct drm_fb_helper_connector *fb_helper_connector =
@@ -145,6 +147,8 @@ fail:
 		fb_helper->connector_info[i] = NULL;
 	}
 	fb_helper->connector_count = 0;
+out:
+	drm_connector_list_iter_put(&conn_iter);
 	mutex_unlock(&dev->mode_config.mutex);
 
 	return ret;
diff --git a/drivers/gpu/drm/drm_modeset_helper.c b/drivers/gpu/drm/drm_modeset_helper.c
index b4f36652fe2a..cc44a9a4b004 100644
--- a/drivers/gpu/drm/drm_modeset_helper.c
+++ b/drivers/gpu/drm/drm_modeset_helper.c
@@ -48,6 +48,7 @@ void drm_helper_move_panel_connectors_to_head(struct drm_device *dev)
 
 	INIT_LIST_HEAD(&panel_list);
 
+	spin_lock_irq(&dev->mode_config.connector_list_lock);
 	list_for_each_entry_safe(connector, tmp,
 				 &dev->mode_config.connector_list, head) {
 		if (connector->connector_type == DRM_MODE_CONNECTOR_LVDS ||
@@ -57,6 +58,7 @@ void drm_helper_move_panel_connectors_to_head(struct drm_device *dev)
 	}
 
 	list_splice(&panel_list, &dev->mode_config.connector_list);
+	spin_unlock_irq(&dev->mode_config.connector_list_lock);
 }
 EXPORT_SYMBOL(drm_helper_move_panel_connectors_to_head);
 
diff --git a/drivers/gpu/drm/drm_plane_helper.c b/drivers/gpu/drm/drm_plane_helper.c
index 191a5f095cf9..8b042a193613 100644
--- a/drivers/gpu/drm/drm_plane_helper.c
+++ b/drivers/gpu/drm/drm_plane_helper.c
@@ -75,6 +75,7 @@ static int get_connectors_for_crtc(struct drm_crtc *crtc,
 {
 	struct drm_device *dev = crtc->dev;
 	struct drm_connector *connector;
+	struct drm_connector_list_iter conn_iter;
 	int count = 0;
 
 	/*
@@ -84,7 +85,8 @@ static int get_connectors_for_crtc(struct drm_crtc *crtc,
 	 */
 	WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_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->encoder && connector->encoder->crtc == crtc) {
 			if (connector_list != NULL && count < num_connectors)
 				*(connector_list++) = connector;
@@ -92,6 +94,7 @@ static int get_connectors_for_crtc(struct drm_crtc *crtc,
 			count++;
 		}
 	}
+	drm_connector_list_iter_put(&conn_iter);
 
 	return count;
 }
diff --git a/drivers/gpu/drm/drm_probe_helper.c b/drivers/gpu/drm/drm_probe_helper.c
index ac953f037be7..7cff91e7497f 100644
--- a/drivers/gpu/drm/drm_probe_helper.c
+++ b/drivers/gpu/drm/drm_probe_helper.c
@@ -129,6 +129,7 @@ void drm_kms_helper_poll_enable_locked(struct drm_device *dev)
 {
 	bool poll = false;
 	struct drm_connector *connector;
+	struct drm_connector_list_iter conn_iter;
 	unsigned long delay = DRM_OUTPUT_POLL_PERIOD;
 
 	WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
@@ -136,11 +137,13 @@ void drm_kms_helper_poll_enable_locked(struct drm_device *dev)
 	if (!dev->mode_config.poll_enabled || !drm_kms_helper_poll)
 		return;
 
-	drm_for_each_connector(connector, dev) {
+	drm_connector_list_iter_get(dev, &conn_iter);
+	drm_for_each_connector_iter(connector, &conn_iter) {
 		if (connector->polled & (DRM_CONNECTOR_POLL_CONNECT |
 					 DRM_CONNECTOR_POLL_DISCONNECT))
 			poll = true;
 	}
+	drm_connector_list_iter_put(&conn_iter);
 
 	if (dev->mode_config.delayed_event) {
 		poll = true;
@@ -382,6 +385,7 @@ static void output_poll_execute(struct work_struct *work)
 	struct delayed_work *delayed_work = to_delayed_work(work);
 	struct drm_device *dev = container_of(delayed_work, struct drm_device, mode_config.output_poll_work);
 	struct drm_connector *connector;
+	struct drm_connector_list_iter conn_iter;
 	enum drm_connector_status old_status;
 	bool repoll = false, changed;
 
@@ -397,8 +401,8 @@ static void output_poll_execute(struct work_struct *work)
 		goto out;
 	}
 
-	drm_for_each_connector(connector, dev) {
-
+	drm_connector_list_iter_get(dev, &conn_iter);
+	drm_for_each_connector_iter(connector, &conn_iter) {
 		/* Ignore forced connectors. */
 		if (connector->force)
 			continue;
@@ -451,6 +455,7 @@ static void output_poll_execute(struct work_struct *work)
 			changed = true;
 		}
 	}
+	drm_connector_list_iter_put(&conn_iter);
 
 	mutex_unlock(&dev->mode_config.mutex);
 
@@ -562,6 +567,7 @@ EXPORT_SYMBOL(drm_kms_helper_poll_fini);
 bool drm_helper_hpd_irq_event(struct drm_device *dev)
 {
 	struct drm_connector *connector;
+	struct drm_connector_list_iter conn_iter;
 	enum drm_connector_status old_status;
 	bool changed = false;
 
@@ -569,8 +575,8 @@ bool drm_helper_hpd_irq_event(struct drm_device *dev)
 		return false;
 
 	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) {
 		/* Only handle HPD capable connectors. */
 		if (!(connector->polled & DRM_CONNECTOR_POLL_HPD))
 			continue;
@@ -586,7 +592,7 @@ bool drm_helper_hpd_irq_event(struct drm_device *dev)
 		if (old_status != connector->status)
 			changed = true;
 	}
-
+	drm_connector_list_iter_put(&conn_iter);
 	mutex_unlock(&dev->mode_config.mutex);
 
 	if (changed)