btrfs-progs: tests/mkfs: verify that mkfs.btrfs rootdir+shrink behaves correctly

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

diff --git a/tests/mkfs-tests/012-rootdir-no-shrink/test.sh b/tests/mkfs-tests/012-rootdir-no-shrink/test.sh
new file mode 100755 (executable)
index 0000000..c1cb04f
--- /dev/null
+++ b/tests/mkfs-tests/012-rootdir-no-shrink/test.sh
@@ -0,0 +1,39 @@
+#!/bin/bash
+# Test if mkfs.btrfs --rootdir will skip shrinking correctly
+
+source "$TOP/tests/common"
+
+check_prereq mkfs.btrfs
+
+setup_root_helper
+
+fs_size=$((512 * 1024 * 1024))
+bs=$((1024 * 1024))
+tmp=$(mktemp -d --tmpdir btrfs-progs-mkfs.rootdirXXXXXXX)
+
+prepare_test_dev $fs_size
+
+# No shrink case
+
+run_check "$TOP/mkfs.btrfs" -f --rootdir "$tmp" "$TEST_DEV"
+run_check_mount_test_dev
+
+# We should be able to write at least half of the fs size data since the fs is
+# not shrunk
+run_check $SUDO_HELPER dd if=/dev/zero bs=$bs count=$(($fs_size / $bs / 2)) \
+       of="$TEST_MNT/file"
+
+run_check_umount_test_dev
+
+# Shrink case
+
+run_check "$TOP/mkfs.btrfs" -f --rootdir "$tmp" --shrink "$TEST_DEV"
+run_check_mount_test_dev
+
+run_mustfail "mkfs.btrfs for shrink rootdir" \
+       $SUDO_HELPER dd if=/dev/zero bs=$bs count=$(($fs_size / $bs / 2)) \
+       of="$TEST_MNT/file"
+
+run_check_umount_test_dev
+
+rm -rf -- "$tmp"