On Mon, Oct 21, 2019 at 05:37:52PM +0800, Qu Wenruo wrote: > Before this patchset, if we want to use backup roots, it's only possible > to let btrfs-check to automatically choose the backup. > > If user want to use a specified backup, it can only use -r|--tree-root > option along with backup roots dump from "btrfs ins dump-super". > > This patchset will introduce optional argument for -b|--backup, so user > can specify which backup to use by providing the generation difference > (-3, -2, -1). Please don't introduce the optional arguments. I think we've learned the lesson with 'defrag -c' or balance -d/-m arguments. In this case a long option would be fine as the backup roots is not something that's used often. We can keep the --backup as "use first good" and add the more specific selection.
