pnfsblock: set read/write tk_status to pnfs_error

To pass the IO status to upper layer.
Signed-off-by: NPeng Tao <peng_tao@emc.com>
Signed-off-by: NBenny Halevy <bhalevy@tonian.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

fs/nfs/blocklayout/blocklayout.c

@@ -216,6 +216,7 @@ bl_end_par_io_read(void *data)
 {
 	struct nfs_read_data *rdata = data;
 
+	rdata->task.tk_status = rdata->pnfs_error;
 	INIT_WORK(&rdata->task.u.tk_work, bl_read_cleanup);
 	schedule_work(&rdata->task.u.tk_work);
 }
@@ -405,7 +406,7 @@ static void bl_end_par_io_write(void *data)
 {
 	struct nfs_write_data *wdata = data;
 
-	wdata->task.tk_status = 0;
+	wdata->task.tk_status = wdata->pnfs_error;
 	wdata->verf.committed = NFS_FILE_SYNC;
 	INIT_WORK(&wdata->task.u.tk_work, bl_write_cleanup);
 	schedule_work(&wdata->task.u.tk_work);