NTB: Fix ntb_transport link down race

[cascardo/linux.git] / drivers / ntb / ntb_transport.c

diff --git a/drivers/ntb/ntb_transport.c b/drivers/ntb/ntb_transport.c
index 12a9e83..7010f23 100644 (file)
--- a/drivers/ntb/ntb_transport.c
+++ b/drivers/ntb/ntb_transport.c
@@ -584,11 +584,8 @@ static int ntb_set_mw(struct ntb_transport *nt, int num_mw, unsigned int size)
        return 0;
 }
 
-static void ntb_qp_link_cleanup(struct work_struct *work)
+static void ntb_qp_link_cleanup(struct ntb_transport_qp *qp)
 {
-       struct ntb_transport_qp *qp = container_of(work,
-                                                  struct ntb_transport_qp,
-                                                  link_cleanup);
        struct ntb_transport *nt = qp->transport;
        struct pci_dev *pdev = ntb_query_pdev(nt->ndev);
 
@@ -602,6 +599,16 @@ static void ntb_qp_link_cleanup(struct work_struct *work)
 
        dev_info(&pdev->dev, "qp %d: Link Down\n", qp->qp_num);
        qp->qp_link = NTB_LINK_DOWN;
+}
+
+static void ntb_qp_link_cleanup_work(struct work_struct *work)
+{
+       struct ntb_transport_qp *qp = container_of(work,
+                                                  struct ntb_transport_qp,
+                                                  link_cleanup);
+       struct ntb_transport *nt = qp->transport;
+
+       ntb_qp_link_cleanup(qp);
 
        if (nt->transport_link == NTB_LINK_UP)
                schedule_delayed_work(&qp->link_work,
@@ -613,22 +620,20 @@ static void ntb_qp_link_down(struct ntb_transport_qp *qp)
        schedule_work(&qp->link_cleanup);
 }
 
-static void ntb_transport_link_cleanup(struct work_struct *work)
+static void ntb_transport_link_cleanup(struct ntb_transport *nt)
 {
-       struct ntb_transport *nt = container_of(work, struct ntb_transport,
-                                               link_cleanup);
        int i;
 
+       /* Pass along the info to any clients */
+       for (i = 0; i < nt->max_qps; i++)
+               if (!test_bit(i, &nt->qp_bitmap))
+                       ntb_qp_link_cleanup(&nt->qps[i]);
+
        if (nt->transport_link == NTB_LINK_DOWN)
                cancel_delayed_work_sync(&nt->link_work);
        else
                nt->transport_link = NTB_LINK_DOWN;
 
-       /* Pass along the info to any clients */
-       for (i = 0; i < nt->max_qps; i++)
-               if (!test_bit(i, &nt->qp_bitmap))
-                       ntb_qp_link_down(&nt->qps[i]);
-
        /* The scratchpad registers keep the values if the remote side
         * goes down, blast them now to give them a sane value the next
         * time they are accessed
@@ -637,6 +642,14 @@ static void ntb_transport_link_cleanup(struct work_struct *work)
                ntb_write_local_spad(nt->ndev, i, 0);
 }
 
+static void ntb_transport_link_cleanup_work(struct work_struct *work)
+{
+       struct ntb_transport *nt = container_of(work, struct ntb_transport,
+                                               link_cleanup);
+
+       ntb_transport_link_cleanup(nt);
+}
+
 static void ntb_transport_event_callback(void *data, enum ntb_hw_event event)
 {
        struct ntb_transport *nt = data;
@@ -880,7 +893,7 @@ static int ntb_transport_init_queue(struct ntb_transport *nt,
        }
 
        INIT_DELAYED_WORK(&qp->link_work, ntb_qp_link_work);
-       INIT_WORK(&qp->link_cleanup, ntb_qp_link_cleanup);
+       INIT_WORK(&qp->link_cleanup, ntb_qp_link_cleanup_work);
 
        spin_lock_init(&qp->ntb_rx_pend_q_lock);
        spin_lock_init(&qp->ntb_rx_free_q_lock);
@@ -936,7 +949,7 @@ int ntb_transport_init(struct pci_dev *pdev)
        }
 
        INIT_DELAYED_WORK(&nt->link_work, ntb_transport_link_work);
-       INIT_WORK(&nt->link_cleanup, ntb_transport_link_cleanup);
+       INIT_WORK(&nt->link_cleanup, ntb_transport_link_cleanup_work);
 
        rc = ntb_register_event_callback(nt->ndev,
                                         ntb_transport_event_callback);
@@ -972,7 +985,7 @@ void ntb_transport_free(void *transport)
        struct ntb_device *ndev = nt->ndev;
        int i;
 
-       nt->transport_link = NTB_LINK_DOWN;
+       ntb_transport_link_cleanup(nt);
 
        /* verify that all the qp's are freed */
        for (i = 0; i < nt->max_qps; i++) {