On Wed, 11 Oct 2023 at 10:45, Amir Goldstein <amir73il@xxxxxxxxx> wrote: > > We could add new keys: > lowerdir_first=,lowerdir_next=,lowerdatadir_next= > as explicit variants for the "[^:]",":","::" prefix detection > and those don't need to be unescaped. Good idea. I'd merge "lowerdir_first" and "lowerdir_next" into "lowerdir_one" or whatever for simplicity. I'd also consider dropping the prefix detection, since it has only been in mainline for one cycle. > > > > > > Anyway, let's focus on what you would like best. > > > If you prefer to just fix the regression, it is doable. > > > If you prefer the upperdirfd, workdirfd, lowerdirfd API, I think we can > > > find a volunteer to write it up. > > > > It's not all good: when showing these options, the result is > > completely meaningless. Or is there a plan to make that work nicely? > > > > Currently, the paths to display in mount options are stored > in ofs->config.lowerdirs array. > > Those paths could be invalid or point to different objects or not > accessible from the mount namepsace by the time someone > observes them in mount options, so there are not many guarantees > about those displayed paths. > > We could use file_path() to resolve path strings of the moment in the > mount namepsace of the mounter from the lowerdirfd files and store > them in ofs->config.lowerdirs array. Right, so the configuration would use fd's while the display would fall back to string paths. That makes sense. > BTW, it looks like we also don't display the user passed lowerdir > parameter as is in the case of escaped characters in lowerdirs. > Admittedly, that is another change of behavior from the new mount > api param parsers. And it's a bug (regardless of being a regression or not) since commas and whitespace must be escaped on this interface, and colon too for being a separator of lower layers. More fun: upperdir and workdir use seq_show_option() which escapes commas and whitespace, so any escaped characters during mount will end up being double escaped. Obviously this domain is severely undertested. Thanks, Miklos
