RDMA/vmw_pvrdma: Report CQ missed events

There is a chance of a race between arming the CQ and receiving
completions. By reporting CQ missed events any ULPs should poll
again to get the completions.

Fixes: 29c8d9eba550 ("IB: Add vmw_pvrdma driver")
Acked-by: Aditya Sarwade <asarwade@vmware.com>
Signed-off-by: Bryan Tan <bryantan@vmware.com>
Signed-off-by: Adit Ranadive <aditr@vmware.com>
Reviewed-by: Yuval Shaia <yuval.shaia@oracle.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

1 files changed, 16 insertions, 1 deletions

diff --git a/drivers/infiniband/hw/vmw_pvrdma/pvrdma_cq.c b/drivers/infiniband/hw/vmw_pvrdma/pvrdma_cq.c
index 69bda611d313..90aa326fd7c0 100644
--- a/drivers/infiniband/hw/vmw_pvrdma/pvrdma_cq.c
+++ b/drivers/infiniband/hw/vmw_pvrdma/pvrdma_cq.c
@@ -65,13 +65,28 @@ int pvrdma_req_notify_cq(struct ib_cq *ibcq,
         struct pvrdma_dev *dev = to_vdev(ibcq->device);
         struct pvrdma_cq *cq = to_vcq(ibcq);
         u32 val = cq->cq_handle;
+        unsigned long flags;
+        int has_data = 0;
 
         val |= (notify_flags & IB_CQ_SOLICITED_MASK) == IB_CQ_SOLICITED ?
                 PVRDMA_UAR_CQ_ARM_SOL : PVRDMA_UAR_CQ_ARM;
 
+        spin_lock_irqsave(&cq->cq_lock, flags);
+
         pvrdma_write_uar_cq(dev, val);
 
-        return 0;
+        if (notify_flags & IB_CQ_REPORT_MISSED_EVENTS) {
+                unsigned int head;
+
+                has_data = pvrdma_idx_ring_has_data(&cq->ring_state->rx,
+                                                    cq->ibcq.cqe, &head);
+                if (unlikely(has_data == PVRDMA_INVALID_IDX))
+                        dev_err(&dev->pdev->dev, "CQ ring state invalid\n");
+        }
+
+        spin_unlock_irqrestore(&cq->cq_lock, flags);
+
+        return has_data;
 }
 
 /**