btrfs-progs: tests: convert: add a test case to check the csum for the image file

The new test case would create an empty ext4 with 64K block size, which
can lead to a new data chunk which is no longer 1:1 mapped.

Then convert the fs and verify it with --check-data-csum to make sure
the image file is fine.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

Author: adam900710

tests/convert-tests/023-64k-blocksize-migrated/test.sh

@@ -0,0 +1,16 @@
+#!/bin/bash
+# Make sure the migrated range doesn't cause csum errors
+
+source "$TEST_TOP/common" || exit
+source "$TEST_TOP/common.convert" || exit
+
+setup_root_helper
+prepare_test_dev 10G
+
+check_global_prereq mkfs.ext4
+check_prereq btrfs-convert
+check_prereq btrfs
+
+run_check mkfs.ext4 -b 64K -F "$TEST_DEV"
+run_check $SUDO_HELPER "$TOP/btrfs-convert" --nodesize 64K "$TEST_DEV"
+run_check $SUDO_HELPER "$TOP/btrfs" check --check-data-csum "$TEST_DEV"