vdev_read
if (vdev_probe(vdev_read, NULL, tdev, &spa) != 0) {
static int vdev_read(void *vdev __unused, void *priv, off_t off, void *buf,
gdsk.gdev = geli_taste(vdev_read, &gdsk.dsk,
return (vdev_read(NULL, (void *)(uintptr_t)ppa->fd,
ret = vdev_probe(vdev_read, vdev_write, (void *)(uintptr_t)fd, &spa);
if (vdev_probe(vdev_read, NULL, &fd[i - 1], NULL) != 0) {