On Sun, Aug 30, 2020 at 9:10 PM Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote: > > On Sun, Aug 30, 2020 at 09:05:40PM +0200, Miklos Szeredi wrote: > > 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. > > I think fiemap() should be allowed on a stream. After all, these extents > do exist. But I'm opposed to allowing getdents(); it'll only encourage > people to think they can have non-files as streams. Call it whatever you want. I think getdents (without lseek!!!) is a fine interface for enumeration. Also let me stress again, that this ALT thing is not just about streams, but a generic interface for getting OOB/meta/whatever data for a given inode/path. Hence it must have a depth of at least 2, but limiting it to 2 would again be shortsighted. Thanks, Miklos
