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>

diff --git a/net/ncsi/ncsi-aen.c b/net/ncsi/ncsi-aen.c
index b41a661..6898e72 100644 (file)
--- 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);