btrfs-progs: tests: Test if btrfs-image can handle RAID1 missing device

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

tests/misc-tests/030-missing-device-image/test.sh

@@ -0,0 +1,58 @@
+#!/bin/bash
+# Test that btrfs-image can dump image correctly for a missing device (RAID1)
+#
+# At least for RAID1, btrfs-image should be able to handle one missing device
+# without any problem
+
+source "$TEST_TOP/common"
+
+check_prereq btrfs-image
+check_prereq mkfs.btrfs
+check_prereq btrfs
+
+setup_root_helper
+setup_loopdevs 2
+prepare_loopdevs
+dev1=${loopdevs[1]}
+dev2=${loopdevs[2]}
+
+# $1:	device number to remove (either 1 or 2)
+test_missing()
+{
+	local bad_num
+	local bad_dev
+	local good_num
+	local good_dev
+
+	bad_num=$1
+	bad_dev=${loopdevs[$bad_num]}
+	good_num=$((3 - $bad_num))
+	good_dev=${loopdevs[$good_num]}
+
+	run_check $SUDO_HELPER "$TOP/mkfs.btrfs" -f -d raid1 -m raid1 "$dev1" "$dev2"
+
+	# fill the fs with some data, we could create space cache
+	run_check $SUDO_HELPER mount "$dev1" "$TEST_MNT"
+	run_check $SUDO_HELPER dd if=/dev/zero of="$TEST_MNT/a" bs=1M count=10
+	run_check $SUDO_HELPER dd if=/dev/zero of="$TEST_MNT/b" bs=4k count=1000 conv=sync
+	run_check $SUDO_HELPER umount "$TEST_MNT"
+
+	# make sure we have space cache
+	if ! run_check_stdout "$TOP/btrfs" inspect dump-tree -t root "$dev1" |
+		grep -q "EXTENT_DATA"; then
+		# Normally the above operation should create the space cache.
+		# If not, it may mean we have migrated to v2 cache by default
+		_not_run "unable to create v1 space cache"
+	fi
+
+	# now wipe the device
+	run_check wipefs -fa "$bad_dev"
+
+	# we don't care about the image but btrfs-image must not fail
+	run_check "$TOP/btrfs-image" "$good_dev" /dev/null
+}
+
+# Test with either device missing, so we're ensured to hit missing device
+test_missing 1
+test_missing 2
+cleanup_loopdevs