pNFS/flexfiles: Report RDMA connection errors to the server

commit 7836d75 upstream.

The RPC/RDMA driver will return -EPROTO and -ENODEV as connection errors
under certain circumstances. Make sure that we handle them and report
them to the server. If not, we can end up cycling forever in a
LAYOUTGET/LAYOUTRETURN loop.

Fixes: a12f996 ("NFSv4/pNFS: Use connections to a DS that are all of the same protocol family")
Cc: stable@vger.kernel.org # 5.11.x
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

fs/nfs/flexfilelayout/flexfilelayout.c

@@ -1140,6 +1140,8 @@ static int ff_layout_async_handle_error_v4(struct rpc_task *task,
 	case -EIO:
 	case -ETIMEDOUT:
 	case -EPIPE:
+	case -EPROTO:
+	case -ENODEV:
 		dprintk("%s DS connection error %d\n", __func__,
 			task->tk_status);
 		nfs4_delete_deviceid(devid->ld, devid->nfs_client,
@@ -1245,6 +1247,8 @@ static void ff_layout_io_track_ds_error(struct pnfs_layout_segment *lseg,
 		case -ENOBUFS:
 		case -EPIPE:
 		case -EPERM:
+		case -EPROTO:
+		case -ENODEV:
 			*op_status = status = NFS4ERR_NXIO;
 			break;
 		case -EACCES: