net/ncsi: Improve HNCDSC AEN handler

This improves AEN handler for Host Network Controller Driver Status
Change (HNCDSC):

   * The channel's lock should be hold when accessing its state.
   * Do failover when host driver isn't ready.
   * Configure channel when host driver becomes ready.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 15 insertions, 3 deletions

diff --git a/net/ncsi/ncsi-aen.c b/net/ncsi/ncsi-aen.c
index b41a6617d498..6898e7229285 100644
--- a/net/ncsi/ncsi-aen.c
+++ b/net/ncsi/ncsi-aen.c
@@ -141,23 +141,35 @@ static int ncsi_aen_handler_hncdsc(struct ncsi_dev_priv *ndp,
                 return -ENODEV;
 
         /* If the channel is active one, we need reconfigure it */
+        spin_lock_irqsave(&nc->lock, flags);
         ncm = &nc->modes[NCSI_MODE_LINK];
         hncdsc = (struct ncsi_aen_hncdsc_pkt *)h;
         ncm->data[3] = ntohl(hncdsc->status);
         if (!list_empty(&nc->link) ||
-            nc->state != NCSI_CHANNEL_ACTIVE ||
-            (ncm->data[3] & 0x1))
+            nc->state != NCSI_CHANNEL_ACTIVE) {
+                spin_unlock_irqrestore(&nc->lock, flags);
                 return 0;
+        }
 
-        if (ndp->flags & NCSI_DEV_HWA)
+        spin_unlock_irqrestore(&nc->lock, flags);
+        if (!(ndp->flags & NCSI_DEV_HWA) && !(ncm->data[3] & 0x1))
                 ndp->flags |= NCSI_DEV_RESHUFFLE;
 
         /* If this channel is the active one and the link doesn't
          * work, we have to choose another channel to be active one.
          * The logic here is exactly similar to what we do when link
          * is down on the active channel.
+         *
+         * On the other hand, we need configure it when host driver
+         * state on the active channel becomes ready.
          */
         ncsi_stop_channel_monitor(nc);
+
+        spin_lock_irqsave(&nc->lock, flags);
+        nc->state = (ncm->data[3] & 0x1) ? NCSI_CHANNEL_INACTIVE :
+                                           NCSI_CHANNEL_ACTIVE;
+        spin_unlock_irqrestore(&nc->lock, flags);
+
         spin_lock_irqsave(&ndp->lock, flags);
         list_add_tail_rcu(&nc->link, &ndp->channel_queue);
         spin_unlock_irqrestore(&ndp->lock, flags);