Created attachment 235027 [details] add dev_offset Usually NTFS volume located on device at some offset. We can use losetup/mdconfig for map device from offset to another device and mount this device. But there are some problems: It is new resourse, which has limited && can be leak Method of mount is not portabled Need copy data twice: for loop device and fuse If we pass argument for device offset we can avoid such problems. There is patch to implement this.
Cross-reference (in the read-only mirror): <https://github.com/freebsd/freebsd-ports/pull/128>.
Why submit this patch to FreeBSD instead of fusefs-ntfs upstream?
Let's ask for review someone who updated this port in the past. (In reply to Gleb Popov from comment #2) The URL field of this bug links to an upstream issue with an unmerged pull request.
(In reply to Konstantin Germanov from comment #0) > Need copy data twice: for loop device and fuse Have you measured the actual overhead of this extra layer under real workload? Admittedly, I tend to agree with upstream that this patch (or rather, eight patches) is dubious and does not solve something otherwise unsolvable. Keeping this size of patchset in the port means we'd have to resolve potential conflicts upon updates and provide support/bugfixes for this custom code, that's something we'd want to avoid. If it would be merged upstream but e.g. disabled by default, we could enable it in the port, but keeping big chunks of code in the port itself is bad practice.
I'd like to add that we already have perfectly working geom_map(4) that allows us to define /dev/map/NAME over existing GEOM using offsets and kenv(1) utility, then use such /dev/map/NAME for ntfs or anything else.
Closing per comment #5, geom_map(4) does exactly what you need with zero overhead.