Add bdev_destroy() and bdev_destroy_wrapper()

src/lxc/bdev.c

@@ -3614,3 +3614,40 @@ bool rootfs_is_blockdev(struct lxc_conf *conf)
 		return true;
 	return false;
 }
+
+bool bdev_destroy(struct lxc_conf *conf)
+{
+	struct bdev *r;
+	bool ret = false;
+
+	r = bdev_init(conf, conf->rootfs.path, conf->rootfs.mount, NULL);
+	if (!r)
+		return ret;
+
+	if (r->ops->destroy(r) == 0)
+		ret = true;
+	bdev_put(r);
+
+	return ret;
+}
+
+int bdev_destroy_wrapper(void *data)
+{
+	struct lxc_conf *conf = data;
+
+	if (setgid(0) < 0) {
+		ERROR("Failed to setgid to 0");
+		return -1;
+	}
+	if (setgroups(0, NULL) < 0)
+		WARN("Failed to clear groups");
+	if (setuid(0) < 0) {
+		ERROR("Failed to setuid to 0");
+		return -1;
+	}
+	if (!bdev_destroy(conf))
+		return -1;
+	else
+		return 0;
+}
+

src/lxc/bdev.h

@@ -123,6 +123,9 @@ struct bdev *bdev_copy(struct lxc_container *c0, const char *cname,
 struct bdev *bdev_create(const char *dest, const char *type,
 			const char *cname, struct bdev_specs *specs);
 void bdev_put(struct bdev *bdev);
+bool bdev_destroy(struct lxc_conf *conf);
+/* callback function to be used with userns_exec_1() */
+int bdev_destroy_wrapper(void *data);
 
 /*
  * these are really for qemu-nbd support, as container shutdown