This tests ensures that the kernel correctly persists backup roots in
case the filesystem has been mounted from a backup root.
Signed-off-by: Nikolay Borisov <nborisov@xxxxxxxx>
---
.../misc-tests/038-backup-root-corruption/test.sh | 50 ++++++++++++++++++++++
1 file changed, 50 insertions(+)
create mode 100755 tests/misc-tests/038-backup-root-corruption/test.sh
diff --git a/tests/misc-tests/038-backup-root-corruption/test.sh b/tests/misc-tests/038-backup-root-corruption/test.sh
new file mode 100755
index 000000000000..2fb117b3a928
--- /dev/null
+++ b/tests/misc-tests/038-backup-root-corruption/test.sh
@@ -0,0 +1,50 @@
+#!/bin/bash
+# Test that a corrupted filesystem will correctly handle writing of
+# backup root
+
+source "$TEST_TOP/common"
+
+check_prereq mkfs.btrfs
+check_prereq btrfs
+check_prereq btrfs-corrupt-block
+
+setup_loopdevs 1
+prepare_loopdevs
+dev=${loopdevs[1]}
+
+run_check $SUDO_HELPER "$TOP/mkfs.btrfs" -f "$dev"
+
+# Create a file and unmount to commit some backup roots
+run_check $SUDO_HELPER mount "$dev" "$TEST_MNT"
+run_check touch "$TEST_MNT/file" && sync
+run_check $SUDO_HELPER umount "$TEST_MNT"
+
+# Ensure currently active backup slot is the expected one (slot 3)
+backup2_root_ptr=$($SUDO_HELPER "$TOP/btrfs" inspect-internal dump-super -f "$dev" \
+ | grep -A1 "backup 2" | grep backup_tree_root | awk '{print $2}')
+
+main_root_ptr=$($SUDO_HELPER "$TOP/btrfs" inspect-internal dump-super -f "$dev" \
+ | grep root | head -n1 | awk '{print $2}')
+
+[[ "$backup2_root_ptr" -eq "$main_root_ptr" ]] || _fail "Backup slot 2 is not in use"
+
+run_check "$TOP/btrfs-corrupt-block" -m $main_root_ptr -f generation "$dev"
+
+## should fail because the root is corrupted
+run_mustfail "Unexpected successful mount" $SUDO_HELPER mount "$dev" "$TEST_MNT"
+
+# Cycle mount with the backup to force rewrite of slot 3
+run_check $SUDO_HELPER mount -ousebackuproot "$dev" "$TEST_MNT"
+run_check $SUDO_HELPER umount "$TEST_MNT"
+
+
+# Since we've used backup 1 as the usable root, then backup 2 should have been
+# overwritten
+main_root_ptr=$($SUDO_HELPER "$TOP/btrfs" inspect-internal dump-super -f "$dev" \
+ | grep root | head -n1 | awk '{print $2}')
+backup2_new_root_ptr=$($SUDO_HELPER "$TOP/btrfs" inspect-internal dump-super -f "$dev" \
+ | grep -A1 "backup 2" | grep backup_tree_root | awk '{print $2}')
+
+[[ "$backup2_root_ptr" -ne "$backup2_new_root_ptr" ]] || _fail "Backup 2 not overwritten"
+
+cleanup_loopdevs
--
2.7.4
