btrfs-progs: tests: add test to ensure the restored image can be mounted

This new test case is to make sure the restored image file has been
properly enlarged so that newer kernel won't complain.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

tests/misc-tests/048-image-restore-mount/test.sh

@@ -0,0 +1,21 @@
+#!/bin/bash
+# Verify that the restored image of an empty btrfs filesystem can still be
+# mounted
+
+source "$TEST_TOP/common"
+
+check_prereq btrfs-image
+check_prereq mkfs.btrfs
+check_prereq btrfs
+
+prepare_test_dev
+
+tmp=$(mktemp -d --tmpdir btrfs-progs-image.XXXXXXXX)
+
+run_check_mkfs_test_dev
+run_check "$TOP/btrfs-image" "$TEST_DEV" "$tmp/dump"
+run_check "$TOP/btrfs-image" -r "$tmp/dump" "$tmp/restored"
+run_check $SUDO_HELPER mount -t btrfs -o loop "$tmp/restored" "$TEST_MNT"
+run_check $SUDO_HELPER umount "$TEST_MNT"
+
+rm -rf -- "$tmp"