1 files changed, 76 insertions, 4 deletions

diff --git a/drivers/infiniband/hw/cxgb3/iwch.c b/drivers/infiniband/hw/cxgb3/iwch.c
index b0ea0105ddf6..ee1d8b4d4541 100644
--- a/drivers/infiniband/hw/cxgb3/iwch.c
+++ b/drivers/infiniband/hw/cxgb3/iwch.c
@@ -65,6 +65,46 @@ struct cxgb3_client t3c_client = {
 static LIST_HEAD(dev_list);
 static DEFINE_MUTEX(dev_mutex);
 
+static int disable_qp_db(int id, void *p, void *data)
+{
+        struct iwch_qp *qhp = p;
+
+        cxio_disable_wq_db(&qhp->wq);
+        return 0;
+}
+
+static int enable_qp_db(int id, void *p, void *data)
+{
+        struct iwch_qp *qhp = p;
+
+        if (data)
+                ring_doorbell(qhp->rhp->rdev.ctrl_qp.doorbell, qhp->wq.qpid);
+        cxio_enable_wq_db(&qhp->wq);
+        return 0;
+}
+
+static void disable_dbs(struct iwch_dev *rnicp)
+{
+        spin_lock_irq(&rnicp->lock);
+        idr_for_each(&rnicp->qpidr, disable_qp_db, NULL);
+        spin_unlock_irq(&rnicp->lock);
+}
+
+static void enable_dbs(struct iwch_dev *rnicp, int ring_db)
+{
+        spin_lock_irq(&rnicp->lock);
+        idr_for_each(&rnicp->qpidr, enable_qp_db,
+                     (void *)(unsigned long)ring_db);
+        spin_unlock_irq(&rnicp->lock);
+}
+
+static void iwch_db_drop_task(struct work_struct *work)
+{
+        struct iwch_dev *rnicp = container_of(work, struct iwch_dev,
+                                              db_drop_task.work);
+        enable_dbs(rnicp, 1);
+}
+
 static void rnic_init(struct iwch_dev *rnicp)
 {
         PDBG("%s iwch_dev %p\n", __func__,  rnicp);
@@ -72,6 +112,7 @@ static void rnic_init(struct iwch_dev *rnicp)
         idr_init(&rnicp->qpidr);
         idr_init(&rnicp->mmidr);
         spin_lock_init(&rnicp->lock);
+        INIT_DELAYED_WORK(&rnicp->db_drop_task, iwch_db_drop_task);
 
         rnicp->attr.max_qps = T3_MAX_NUM_QP - 32;
         rnicp->attr.max_wrs = T3_MAX_QP_DEPTH;
@@ -147,6 +188,8 @@ static void close_rnic_dev(struct t3cdev *tdev)
         mutex_lock(&dev_mutex);
         list_for_each_entry_safe(dev, tmp, &dev_list, entry) {
                 if (dev->rdev.t3cdev_p == tdev) {
+                        dev->rdev.flags = CXIO_ERROR_FATAL;
+                        cancel_delayed_work_sync(&dev->db_drop_task);
                         list_del(&dev->entry);
                         iwch_unregister_device(dev);
                         cxio_rdev_close(&dev->rdev);
@@ -165,7 +208,8 @@ static void iwch_event_handler(struct t3cdev *tdev, u32 evt, u32 port_id)
         struct cxio_rdev *rdev = tdev->ulp;
         struct iwch_dev *rnicp;
         struct ib_event event;
-        u32    portnum = port_id + 1;
+        u32 portnum = port_id + 1;
+        int dispatch = 0;
 
         if (!rdev)
                 return;
@@ -174,21 +218,49 @@ static void iwch_event_handler(struct t3cdev *tdev, u32 evt, u32 port_id)
         case OFFLOAD_STATUS_DOWN: {
                 rdev->flags = CXIO_ERROR_FATAL;
                 event.event  = IB_EVENT_DEVICE_FATAL;
+                dispatch = 1;
                 break;
                 }
         case OFFLOAD_PORT_DOWN: {
                 event.event  = IB_EVENT_PORT_ERR;
+                dispatch = 1;
                 break;
                 }
         case OFFLOAD_PORT_UP: {
                 event.event  = IB_EVENT_PORT_ACTIVE;
+                dispatch = 1;
+                break;
+                }
+        case OFFLOAD_DB_FULL: {
+                disable_dbs(rnicp);
+                break;
+                }
+        case OFFLOAD_DB_EMPTY: {
+                enable_dbs(rnicp, 1);
+                break;
+                }
+        case OFFLOAD_DB_DROP: {
+                unsigned long delay = 1000;
+                unsigned short r;
+
+                disable_dbs(rnicp);
+                get_random_bytes(&r, 2);
+                delay += r & 1023;
+
+                /*
+                 * delay is between 1000-2023 usecs.
+                 */
+                schedule_delayed_work(&rnicp->db_drop_task,
+                        usecs_to_jiffies(delay));
                 break;
                 }
         }
 
-        event.device = &rnicp->ibdev;
-        event.element.port_num = portnum;
-        ib_dispatch_event(&event);
+        if (dispatch) {
+                event.device = &rnicp->ibdev;
+                event.element.port_num = portnum;
+                ib_dispatch_event(&event);
+        }
 
         return;
 }