NFSv4.1: Try to deal with NFS4ERR_SEQ_MISORDERED.

If the server returns NFS4ERR_SEQ_MISORDERED, it could be a sign
that the slot was retired at some point. Retry the attempt after
reinitialising the slot sequence number to 1.

Also add a handler for NFS4ERR_SEQ_FALSE_RETRY. Just bump the slot
sequence number and retry...

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index b0963ae..9003b8f 100644 (file)
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -467,11 +467,19 @@ static int nfs41_sequence_done(struct rpc_task *task, struct nfs4_sequence_res *
                 * The slot id we used was probably retired. Try again
                 * using a different slot id.
                 */
-               if (rpc_restart_call_prepare(task)) {
-                       task->tk_status = 0;
-                       ret = 0;
-               }
-               break;
+               goto retry_nowait;
+       case -NFS4ERR_SEQ_MISORDERED:
+               /*
+                * Could this slot have been previously retired?
+                * If so, then the server may be expecting seq_nr = 1!
+                */
+               if (slot->seq_nr == 1)
+                       break;
+               slot->seq_nr = 1;
+               goto retry_nowait;
+       case -NFS4ERR_SEQ_FALSE_RETRY:
+               ++slot->seq_nr;
+               goto retry_nowait;
        default:
                /* Just update the slot sequence no. */
                ++slot->seq_nr;
@@ -481,6 +489,12 @@ out:
        dprintk("%s: Error %d free the slot \n", __func__, res->sr_status);
        nfs41_sequence_free_slot(res);
        return ret;
+retry_nowait:
+       if (rpc_restart_call_prepare(task)) {
+               task->tk_status = 0;
+               ret = 0;
+       }
+       goto out;
 out_retry:
        if (!rpc_restart_call(task))
                goto out;