@@ -722,6 +722,53 @@ _mkfs_dev()
     rm -f $tmp.mkfserr $tmp.mkfsstd
 }
 
+_set_mkfs_options_blocksized()
+{
+	local blocksize=$1
+	local re='^[0-9]+$'
+
+	if ! [[ $blocksize =~ $re ]]; then
+		_notrun "error _set_mkfs_options_blocksized: blocksize \"$blocksize\" not an integer"
+	fi
+
+	case $FSTYP in
+	btrfs)
+		test -f /sys/fs/btrfs/features/supported_sectorsizes || \
+		_notrun "Subpage sectorsize support is not found in $FSTYP"
+
+		grep -wq $blocksize /sys/fs/btrfs/features/supported_sectorsizes || \
+		_notrun "$FSTYP does not support sectorsize=$blocksize yet"
+
+		MKFS_OPTIONS=" --sectorsize=$blocksize"
+		;;
+	xfs)
+		MKFS_OPTIONS=" -b size=$blocksize"
+		;;
+	ext2|ext3|ext4)
+		MKFS_OPTIONS=" -b $blocksize"
+		;;
+	gfs2)
+		MKFS_OPTIONS=" -O -b $blocksize"
+		;;
+	ocfs2)
+		MKFS_OPTIONS=" -b $blocksize -C $blocksize"
+		;;
+	bcachefs)
+		MKFS_OPTIONS=" --block_size=$blocksize"
+		;;
+	*)
+		# do nothing for other FS.
+		;;
+	esac
+}
+
+_mkfs_dev_blocksized()
+{
+	_set_mkfs_options_blocksized $1
+	shift
+	_mkfs_dev $*
+}
+
 # remove all files in $SCRATCH_MNT, useful when testing on NFS/CIFS
 _scratch_cleanup_files()
 {