I want to determine which subvolume a file or directory is on. For example, if I have a subvolume mount at
/mnt/btrfs-subvol and a directory
/mnt/btrfs-subvol/some/dir and I run
something /mnt/btrfs-subvol/some/dir it returns
The best I can think to do is to walk back, testing each directory with
stat as I go for an inode of 256, but I can't imagine that is the only way of doing this. Or maybe run maybe
until btrfs sub show `pwd`; cd ..;done; echo `pwd`
But I feel there should be a more elegant solution.