NFS: When state recovery fails, waiting tasks should exit

NFSv4 state recovery is not always successful.  Failure is signalled
by setting the nfs_client.cl_cons_state to a negative (errno) value,
then waking waiters.

Currently this can happen only during mount processing.  I'm about to
add an explicit case where state recovery failure during normal
operation should force all NFS requests waiting on that state recovery
to exit.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 80bb5055d0b3c3de96aadb897168633f27472cc0..74dcd85f0a1da8b38c1ba2fb145d80d1d7bc4237 100644 (file)
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -258,7 +258,12 @@ static int nfs4_wait_clnt_recover(struct nfs_client *clp)
 
        res = wait_on_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING,
                        nfs_wait_bit_killable, TASK_KILLABLE);
-       return res;
+       if (res)
+               return res;
+
+       if (clp->cl_cons_state < 0)
+               return clp->cl_cons_state;
+       return 0;
 }
 
 static int nfs4_delay(struct rpc_clnt *clnt, long *timeout)