On Sat, Aug 29, 2020 at 9:25 PM Al Viro <viro@xxxxxxxxxxxxxxxxxx> wrote: > > On Sat, Aug 29, 2020 at 09:13:24PM +0200, Miklos Szeredi wrote: > > > > d_path() is the least of the problems, actually. Directory tree structure on > > > those, OTOH, is a serious problem. If you want to have getdents(2) on that > > > shite, you want an opened descriptor that looks like a directory. And _that_ > > > opens a large can of worms. Because now you have fchdir(2) to cope with, > > > lookups going through /proc/self/fd/<n>/..., etc., etc. > > > > Seriously, nobody wants fchdir(). And getdents() does not imply fchdir(). > > Yes, it does. If it's a directory, fchdir(2) gets to deal with it. > If it's not, no getdents(2). Unless you special-case the damn thing in > said fchdir(2). Huh? f_op->iterate() needed for getdents(2) and i_op->lookup() needed for fchdir(2). Yes, open(..., O_ALT) would be special. Let's call it open_alt(2) to avoid confusion with normal open on a normal filesystem. No special casing anywhere at all. It's a completely new interface that returns a file which either has ->read/write() or ->iterate() and which points to an inode with empty i_ops. Thanks, Miklos
