btrfs-progs: tests: Add tests for changing fsid feature

Add a bunch of tests exercising the new btrfstune functionality. In
particular check that various restrictions are implemented correctly,
test that btrfs-image works as expected and also test the output of
btrfs inspect-internal dump-super is correct.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

tests/misc-tests/034-metadata-uuid/test.sh

@@ -0,0 +1,225 @@
+#!/bin/bash
+
+source "$TEST_TOP/common"
+
+check_prereq mkfs.btrfs
+check_prereq btrfs
+check_prereq btrfstune
+check_prereq btrfs-image
+
+setup_root_helper
+prepare_test_dev
+
+function read_fsid {
+	local dev="$1"
+
+	echo $(run_check_stdout $SUDO_HELPER "$TOP/btrfs" inspect-internal \
+		dump-super "$dev" | awk '/fsid/ {print $2}' | head -n 1)
+}
+
+function read_metadata_uuid {
+	local dev="$1"
+
+	echo $(run_check_stdout $SUDO_HELPER "$TOP/btrfs" inspect-internal \
+		dump-super "$dev" | awk '/metadata_uuid/ {print $2}')
+}
+
+function check_btrfstune {
+	local fsid
+
+	echo "Checking btrfstune logic" >> "$RESULTS"
+	# test with random uuid
+	run_check $SUDO_HELPER "$TOP/btrfstune" -m "$TEST_DEV"
+
+	# check that specific uuid can set
+	run_check $SUDO_HELPER "$TOP/btrfstune" -M d88c8333-a652-4476-b225-2e9284eb59f1 "$TEST_DEV"
+
+	# test that having seed on already changed device doesn't work
+	run_mustfail "Managed to set seed on metadata uuid fs" \
+		$SUDO_HELPER "$TOP/btrfstune" -S 1 "$TEST_DEV"
+
+	# test that setting both seed and -m|M is forbidden
+	run_check $SUDO_HELPER "$TOP/mkfs.btrfs" -f "$TEST_DEV"
+	run_mustfail "Succeeded setting seed and changing fs uuid" \
+		$SUDO_HELPER "$TOP/btrfstune" -S 1 -m "$TEST_DEV"
+
+	# test that having -m|-M on seed device is forbidden
+	run_check $SUDO_HELPER "$TOP/mkfs.btrfs" -f "$TEST_DEV"
+	run_check $SUDO_HELPER "$TOP/btrfstune" -S 1 "$TEST_DEV"
+	run_mustfail "Succeded changing fsid on a seed device" $SUDO_HELPER "$TOP/btrfstune" -m "$TEST_DEV"
+
+	# test that using -U|-u on an fs with METADATA_UUID flag is forbidden
+	run_check $SUDO_HELPER "$TOP/mkfs.btrfs" -f "$TEST_DEV"
+	run_check $SUDO_HELPER "$TOP/btrfstune" -m "$TEST_DEV"
+	run_mustfail "Succeeded triggering FSID rewrite while METADATA_UUID is active" \
+		$SUDO_HELPER "$TOP/btrfstune" -u  "$TEST_DEV"
+
+}
+
+function check_dump_super_output {
+	local fsid
+	local metadata_uuid
+	local dev_item_match
+	local old_metadata_uuid
+
+	echo "Checking dump-super output" >> "$RESULTS"
+	# assert that metadata/fsid match on non-changed fs
+	fsid=$(read_fsid "$TEST_DEV")
+	metadata_uuid=$(read_metadata_uuid "$TEST_DEV")
+	[ "$fsid" = "$metadata_uuid" ] || _fail "fsid ("$fsid") doesn't match metadata_uuid ("$metadata_uuid")"
+
+	dev_item_match=$(run_check_stdout $SUDO_HELPER "$TOP/btrfs" inspect-internal dump-super \
+		"$TEST_DEV" | awk '/dev_item.fsid/ {print $3}')
+
+	[ $dev_item_match = "[match]" ] || _fail "dev_item.fsid doesn't match on non-metadata uuid fs"
+
+
+	echo "Checking output after fsid change" >> "$RESULTS"
+	# change metadatauuid and ensure everything in the output is still correct
+	old_metadata_uuid=$metadata_uuid
+	run_check $SUDO_HELPER "$TOP/btrfstune" -M d88c8333-a652-4476-b225-2e9284eb59f1 "$TEST_DEV"
+	fsid=$(read_fsid "$TEST_DEV")
+	metadata_uuid=$(read_metadata_uuid "$TEST_DEV")
+	dev_item_match=$(run_check_stdout $SUDO_HELPER "$TOP/btrfs" \
+		inspect-internal dump-super "$TEST_DEV" | awk '/dev_item.fsid/ {print $3}')
+
+	[ "$dev_item_match" = "[match]" ] || _fail "dev_item.fsid doesn't match on metadata uuid fs"
+	[ "$fsid" = "d88c8333-a652-4476-b225-2e9284eb59f1" ] || _fail "btrfstune metadata UUID change failed"
+	[ "$old_metadata_uuid" = "$metadata_uuid" ] || _fail "Metadata uuid change unexpectedly"
+
+	echo "Checking for incompat textual representation" >> "$RESULTS"
+	# check for textual output of the new incompat feature
+	run_check_stdout $SUDO_HELPER "$TOP/btrfs" inspect-internal dump-super \
+		"$TEST_DEV" | grep -q METADATA_UUID
+	[ $? -eq 0 ] || _fail "Didn't find textual representation of METADATA_UUID feature"
+
+	echo "Checking setting fsid back to original" >> "$RESULTS"
+	# ensure that  setting the fsid back to the original works
+	run_check $SUDO_HELPER "$TOP/btrfstune" -M "$old_metadata_uuid" "$TEST_DEV"
+
+	fsid=$(read_fsid "$TEST_DEV")
+	metadata_uuid=$(read_metadata_uuid "$TEST_DEV")
+
+	[ "$fsid" = "$metadata_uuid" ] || _fail "FSID and METADATA_UUID don't match"
+	run_check_stdout $SUDO_HELPER "$TOP/btrfs" inspect-internal dump-super \
+		"$TEST_DEV" | grep -q METADATA_UUID
+	[ $? -eq 1 ] || _fail "METADATA_UUID feature still shown as enabled"
+}
+
+function check_image_restore {
+	local metadata_uuid
+	local fsid
+	local fsid_restored
+	local metadata_uuid_restored
+
+	echo "TESTING btrfs-image restore" >> "$RESULTS"
+	run_check $SUDO_HELPER "$TOP/mkfs.btrfs" -f "$TEST_DEV"
+	run_check $SUDO_HELPER "$TOP/btrfstune" -m "$TEST_DEV"
+	fsid=$(read_fsid "$TEST_DEV")
+	metadata_uuid=$(read_metadata_uuid "$TEST_DEV")
+	run_mayfail $SUDO_HELPER "$TOP/btrfs-image" "$TEST_DEV" /tmp/test-img.dump
+	# erase the fs by creating a new one, wipefs is not sufficient as it just
+	# deletes the fs magic string
+	run_check $SUDO_HELPER "$TOP/mkfs.btrfs" -f "$TEST_DEV"
+	run_check $SUDO_HELPER "$TOP/btrfs-image" -r /tmp/test-img.dump "$TEST_DEV"
+	fsid_restored=$(read_fsid "$TEST_DEV")
+	metadata_uuid_restored=$(read_metadata_uuid "$TEST_DEV")
+
+	[ "$fsid" = "$fsid_restored" ] || _fail "FSID don't match after restore"
+	[ "$metadata_uuid" = "$metadata_uuid_restored" ] || _fail "metadata uuids don't match after restore"
+}
+
+function check_inprogress_flag {
+	# check the flag is indeed cleared
+	run_check_stdout $SUDO_HELPER "$TOP/btrfs" inspect-internal dump-super \
+		$1 | grep -q 0x1000000001
+	[ $? -eq 1 ] || _fail "Found BTRFS_SUPER_FLAG_CHANGING_FSID_V2 set for $1"
+
+	run_check_stdout $SUDO_HELPER $TOP/btrfs inspect-internal dump-super \
+		$2 | grep -q 0x1000000001
+	[ $? -eq 1 ] || _fail "Found BTRFS_SUPER_FLAG_CHANGING_FSID_V2 set for $2"
+}
+
+function check_completed {
+	# check that metadata uuid is indeed completed
+	run_check_stdout $SUDO_HELPER "$TOP/btrfs" inspect-internal dump-super \
+		$1 | grep -q METADATA_UUID
+	[ $? -eq 0 ] || _fail "METADATA_UUID not set on $1"
+
+	run_check_stdout $SUDO_HELPER $TOP/btrfs inspect-internal dump-super \
+		$2 | grep -q METADATA_UUID
+	[ $? -eq 0 ] || _fail "METADATA_UUID not set on $2"
+}
+
+function check_multi_fsid_change {
+	check_inprogress_flag $1 $2
+	check_completed $1 $2
+}
+
+function failure_recovery {
+	local image1
+	local image2
+	local loop1
+	local loop2
+	local devcount
+
+	image1=$(extract_image "$1")
+	image2=$(extract_image "$2")
+	loop1=$(run_check_stdout $SUDO_HELPER losetup --find --show "$image1")
+	loop2=$(run_check_stdout $SUDO_HELPER losetup --find --show "$image2")
+
+	# Mount and unmount, on trans commit all disks should be consistent
+	run_check $SUDO_HELPER mount "$loop1" "$TEST_MNT"
+	run_check $SUDO_HELPER umount "$TEST_MNT"
+
+	# perform any specific check
+	$3 "$loop1" "$loop2"
+
+	# cleanup
+	run_check $SUDO_HELPER losetup -d "$loop1"
+	run_check $SUDO_HELPER losetup -d "$loop2"
+	rm -f "$image1" "$image2"
+}
+
+function reload_btrfs {
+	rmmod btrfs
+	modprobe btrfs
+}
+
+# for full coverage we need btrfs to actually be a module
+modinfo btrfs > /dev/null 2>&1 || _not_run "btrfs must be a module"
+modprobe -r btrfs || _not_run "btrfs must be unloadable"
+modprobe btrfs || _not_run "loading btrfs module failed"
+
+run_check $SUDO_HELPER "$TOP/mkfs.btrfs" -f "$TEST_DEV"
+check_btrfstune
+
+run_check $SUDO_HELPER "$TOP/mkfs.btrfs" -f "$TEST_DEV"
+check_dump_super_output
+
+run_check $SUDO_HELPER "$TOP/mkfs.btrfs" -f "$TEST_DEV"
+check_image_restore
+
+# disk1 is an image which has no metadata uuid flags set and disk2 is part of
+# the same fs but has the in-progress flag set. Test that whicever is scanned
+# first will result in consistent filesystem.
+failure_recovery "./disk1.raw.xz" "./disk2.raw.xz" check_inprogress_flag
+reload_btrfs
+failure_recovery "./disk2.raw.xz" "./disk1.raw.xz" check_inprogress_flag
+
+reload_btrfs
+
+# disk4 contains an image in with the in-progress flag set and disk 3 is part
+# of the same filesystem but has both METADATA_UUID incompat and a new
+# metadata uuid set. So disk 3 must always take precedence
+failure_recovery "./disk3.raw.xz" "./disk4.raw.xz" check_completed
+reload_btrfs
+failure_recovery "./disk4.raw.xz" "./disk3.raw.xz" check_completed
+
+# disk5 contains an image which has undergone a successful fsid change more
+# than once, disk6 on the other hand is member of the same filesystem but
+# hasn't completed its last change. Thus it has both the FSID_CHANGING flag set
+# and METADATA_UUID flag set.
+failure_recovery "./disk5.raw.xz" "./disk6.raw.xz" check_multi_fsid_change
+reload_btrfs
+failure_recovery "./disk6.raw.xz" "./disk5.raw.xz" check_multi_fsid_change