expandable RAID-Z

@@ -62,20 +62,22 @@
 typedef void    vdev_close_func_t(vdev_t *vd);
 typedef int     vdev_probe_func_t(vdev_t *vd);
 typedef uint64_t vdev_asize_func_t(vdev_t *vd, uint64_t psize);
 typedef int     vdev_io_start_func_t(zio_t *zio);
 typedef int     vdev_io_done_func_t(zio_t *zio);
-typedef void    vdev_state_change_func_t(vdev_t *vd, int, int);
+typedef void    vdev_state_change_func_t(vdev_t *vd, int fauled, int degraded);
+typedef uint8_t vdev_grid_func_t(vdev_t *vd);
 
 typedef struct vdev_ops {
         vdev_open_func_t                *vdev_op_open;
         vdev_close_func_t               *vdev_op_close;
         vdev_probe_func_t               *vdev_op_probe;
         vdev_asize_func_t               *vdev_op_asize;
         vdev_io_start_func_t            *vdev_op_io_start;
         vdev_io_done_func_t             *vdev_op_io_done;
         vdev_state_change_func_t        *vdev_op_state_change;
+        vdev_grid_func_t                *vdev_op_grid;
         char                            vdev_op_type[16];
         boolean_t                       vdev_op_leaf;
 } vdev_ops_t;
 
 /*