Kernel bump from 4.1.3-rt to 4.1.7-rt.

[kvmfornfv.git] / kernel / drivers / gpu / drm / drm_dp_mst_topology.c

diff --git a/kernel/drivers/gpu/drm/drm_dp_mst_topology.c b/kernel/drivers/gpu/drm/drm_dp_mst_topology.c
index 132581c..b0487c9 100644 (file)
--- a/kernel/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/kernel/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -867,8 +867,16 @@ static void drm_dp_destroy_port(struct kref *kref)
                port->vcpi.num_slots = 0;
 
                kfree(port->cached_edid);
-               if (port->connector)
-                       (*port->mgr->cbs->destroy_connector)(mgr, port->connector);
+
+               /* we can't destroy the connector here, as
+                  we might be holding the mode_config.mutex
+                  from an EDID retrieval */
+               if (port->connector) {
+                       mutex_lock(&mgr->destroy_connector_lock);
+                       list_add(&port->connector->destroy_list, &mgr->destroy_connector_list);
+                       mutex_unlock(&mgr->destroy_connector_lock);
+                       schedule_work(&mgr->destroy_connector_work);
+               }
                drm_dp_port_teardown_pdt(port, port->pdt);
 
                if (!port->input && port->vcpi.vcpi > 0)
@@ -1163,6 +1171,8 @@ static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device(struct drm_dp_mst_
        struct drm_dp_mst_port *port;
        int i;
        /* find the port by iterating down */
+
+       mutex_lock(&mgr->lock);
        mstb = mgr->mst_primary;
 
        for (i = 0; i < lct - 1; i++) {
@@ -1182,6 +1192,7 @@ static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device(struct drm_dp_mst_
                }
        }
        kref_get(&mstb->kref);
+       mutex_unlock(&mgr->lock);
        return mstb;
 }
 
@@ -1189,7 +1200,7 @@ static void drm_dp_check_and_send_link_address(struct drm_dp_mst_topology_mgr *m
                                               struct drm_dp_mst_branch *mstb)
 {
        struct drm_dp_mst_port *port;
-
+       struct drm_dp_mst_branch *mstb_child;
        if (!mstb->link_address_sent) {
                drm_dp_send_link_address(mgr, mstb);
                mstb->link_address_sent = true;
@@ -1204,17 +1215,31 @@ static void drm_dp_check_and_send_link_address(struct drm_dp_mst_topology_mgr *m
                if (!port->available_pbn)
                        drm_dp_send_enum_path_resources(mgr, mstb, port);
 
-               if (port->mstb)
-                       drm_dp_check_and_send_link_address(mgr, port->mstb);
+               if (port->mstb) {
+                       mstb_child = drm_dp_get_validated_mstb_ref(mgr, port->mstb);
+                       if (mstb_child) {
+                               drm_dp_check_and_send_link_address(mgr, mstb_child);
+                               drm_dp_put_mst_branch_device(mstb_child);
+                       }
+               }
        }
 }
 
 static void drm_dp_mst_link_probe_work(struct work_struct *work)
 {
        struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, work);
+       struct drm_dp_mst_branch *mstb;
 
-       drm_dp_check_and_send_link_address(mgr, mgr->mst_primary);
-
+       mutex_lock(&mgr->lock);
+       mstb = mgr->mst_primary;
+       if (mstb) {
+               kref_get(&mstb->kref);
+       }
+       mutex_unlock(&mgr->lock);
+       if (mstb) {
+               drm_dp_check_and_send_link_address(mgr, mstb);
+               drm_dp_put_mst_branch_device(mstb);
+       }
 }
 
 static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr,
@@ -1269,7 +1294,6 @@ retry:
                                goto retry;
                        }
                        DRM_DEBUG_KMS("failed to dpcd write %d %d\n", tosend, ret);
-                       WARN(1, "fail\n");
 
                        return -EIO;
                }
@@ -2632,6 +2656,30 @@ static void drm_dp_tx_work(struct work_struct *work)
        mutex_unlock(&mgr->qlock);
 }
 
+static void drm_dp_destroy_connector_work(struct work_struct *work)
+{
+       struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, destroy_connector_work);
+       struct drm_connector *connector;
+
+       /*
+        * Not a regular list traverse as we have to drop the destroy
+        * connector lock before destroying the connector, to avoid AB->BA
+        * ordering between this lock and the config mutex.
+        */
+       for (;;) {
+               mutex_lock(&mgr->destroy_connector_lock);
+               connector = list_first_entry_or_null(&mgr->destroy_connector_list, struct drm_connector, destroy_list);
+               if (!connector) {
+                       mutex_unlock(&mgr->destroy_connector_lock);
+                       break;
+               }
+               list_del(&connector->destroy_list);
+               mutex_unlock(&mgr->destroy_connector_lock);
+
+               mgr->cbs->destroy_connector(mgr, connector);
+       }
+}
+
 /**
  * drm_dp_mst_topology_mgr_init - initialise a topology manager
  * @mgr: manager struct to initialise
@@ -2651,10 +2699,13 @@ int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr,
        mutex_init(&mgr->lock);
        mutex_init(&mgr->qlock);
        mutex_init(&mgr->payload_lock);
+       mutex_init(&mgr->destroy_connector_lock);
        INIT_LIST_HEAD(&mgr->tx_msg_upq);
        INIT_LIST_HEAD(&mgr->tx_msg_downq);
+       INIT_LIST_HEAD(&mgr->destroy_connector_list);
        INIT_WORK(&mgr->work, drm_dp_mst_link_probe_work);
        INIT_WORK(&mgr->tx_work, drm_dp_tx_work);
+       INIT_WORK(&mgr->destroy_connector_work, drm_dp_destroy_connector_work);
        init_waitqueue_head(&mgr->tx_waitq);
        mgr->dev = dev;
        mgr->aux = aux;
@@ -2679,6 +2730,7 @@ EXPORT_SYMBOL(drm_dp_mst_topology_mgr_init);
  */
 void drm_dp_mst_topology_mgr_destroy(struct drm_dp_mst_topology_mgr *mgr)
 {
+       flush_work(&mgr->destroy_connector_work);
        mutex_lock(&mgr->payload_lock);
        kfree(mgr->payloads);
        mgr->payloads = NULL;