I can try and make a pull-request for udftune, and I can just copy the API for tune2fs. It would work something like: udftune -O read-only device (to set read-only access type) or: udftune -O ^read-only device (to clear read-only access type (aka set rw)) > On Jan 14, 2019, at 4:30 AM, Jan Kara <jack@xxxxxxx> wrote: > > On Mon 14-01-19 13:00:23, Pali Rohár wrote: >> On Monday 14 January 2019 11:30:11 Jan Kara wrote: >>>> As for the case of remounting as rw if the UDF is ro but the device is >>>> rw, I am not sure what the best idea is to deal with this. If this new >>>> behavior doesn't count as a regression, is there any way to end up with a >>>> UDF filesystem as specced by the command above (-m dvd -b 512, so with it >>>> being read-only), but still allow for mounting it as rw if the device >>>> supports it? Does udftools offer a way to manipulate the UDF partition >>>> descriptor flag in a pre-existing filesystem after it had already been >>>> created that I am missing? >>> >>> So I would really prefer to keep the behavior of disallowing remounting >>> read-only partition read write. After all ECMA-167 standard is pretty clear >>> on this saying that for read-only partitions no sectors can be recorded. I >>> understand it is inconvenient if you try to create e.g. a DVD image. So you >>> want partition to be read-only in the end but initially you need it to be >>> writeable so that you can fill-in the contents. >>> >>> Generally I think a clean solution for this is to provide a way in udftools >>> to switch partition read-only / read-write. Also this is how similar things >>> are achieved for other filesystems. Pali, is there a way to switch >>> accessType of a partition on existing media with udftools? If not, can you >>> look into implementing that please? It should be rather straightforward, >>> the biggest question really is which tool should do this... >> >> You are not the first who asked for such functionality in udftools. >> Michael (CCed) already experimented with such thing and "hacked" >> udflabel to switch access type from overwritable to readonly. >> >> I'm not against adding a new tool into udftools project which can >> manipulate UDF access type. Question is design / API of such tool. >> >> Currently udftools has udfinfo tool which prints lot of information >> about UDF filesystem (including access type). But the only tool which >> modifies UDF filesystem in udftools is udflabel. And udflabel is not >> really the proper place for changing access type. >> >> So some new tool for modifying UDF filesystem would be better. Which >> other settings of UDF filesystem could be useful to be modifiable? I'm >> thinking about "udftune" where new features for modification could be >> implemented later too. > > Yes, that sounds good to me and is in line with what tools for other > filesystems have. > > Honza > -- > Jan Kara <jack@xxxxxxxx> > SUSE Labs, CR
