IB/hfi1: Verify port data VLs credits on transition to Armed

There is a window where the FM can read the buffer control table
and decide not to program buffers. When a port goes down, the code
clears the table and if it is not programmed, posted SDMA descriptors
will never complete due to no buffer credits.

Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Alex Estrin <alex.estrin@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

diff --git a/drivers/infiniband/hw/hfi1/chip.c b/drivers/infiniband/hw/hfi1/chip.c
index 4a4405e..8f7ce74 100644 (file)
--- a/drivers/infiniband/hw/hfi1/chip.c
+++ b/drivers/infiniband/hw/hfi1/chip.c
@@ -10490,6 +10490,14 @@ void set_link_down_reason(struct hfi1_pportdata *ppd, u8 lcl_reason,
 }
 
 /*
+ * Verify if BCT for data VLs is non-zero.
+ */
+static inline bool data_vls_operational(struct hfi1_pportdata *ppd)
+{
+       return !!ppd->actual_vls_operational;
+}
+
+/*
  * Change the physical and/or logical link state.
  *
  * Do not call this routine while inside an interrupt.  It contains
@@ -10587,6 +10595,13 @@ int set_link_state(struct hfi1_pportdata *ppd, u32 state)
                if (ppd->host_link_state != HLS_UP_INIT)
                        goto unexpected;
 
+               if (!data_vls_operational(ppd)) {
+                       dd_dev_err(dd,
+                                  "%s: data VLs not operational\n", __func__);
+                       ret = -EINVAL;
+                       break;
+               }
+
                ppd->host_link_state = HLS_UP_ARMED;
                set_logical_state(dd, LSTATE_ARMED);
                ret = wait_logical_linkstate(ppd, IB_PORT_ARMED, 1000);
@@ -14832,7 +14847,6 @@ struct hfi1_devdata *hfi1_init_dd(struct pci_dev *pdev,
                }
                ppd->vls_supported = num_vls;
                ppd->vls_operational = ppd->vls_supported;
-               ppd->actual_vls_operational = ppd->vls_supported;
                /* Set the default MTU. */
                for (vl = 0; vl < num_vls; vl++)
                        dd->vld[vl].mtu = hfi1_max_mtu;

diff --git a/drivers/infiniband/hw/hfi1/intr.c b/drivers/infiniband/hw/hfi1/intr.c
index 9469be9..96845df 100644 (file)
--- a/drivers/infiniband/hw/hfi1/intr.c
+++ b/drivers/infiniband/hw/hfi1/intr.c
@@ -164,6 +164,7 @@ void handle_linkup_change(struct hfi1_devdata *dd, u32 linkup)
                ppd->linkup = 0;
 
                /* clear HW details of the previous connection */
+               ppd->actual_vls_operational = 0;
                reset_link_credits(dd);
 
                /* freeze after a link down to guarantee a clean egress */