Hi! I agree expanding fanotify_event_metadata painful. After all that's the reason why we've invented the additional info records in the first place :). So I agree with putting the id either in a separate info record or overload something in fanotify_event_metadata. On Sun 29-06-25 08:50:05, Amir Goldstein wrote: > I may have mentioned this before, but I'll bring it up again. > If we want to overload event->fd with response id I would consider > allocating response_id with idr_alloc_cyclic() that starts at 256 > and then set event->fd = -response_id. > We want to skip the range -1..-255 because it is used to report > fd open errors with FAN_REPORT_FD_ERROR. I kind of like this. It looks elegant. The only reason I'm hesitating is that as you mentioned with persistent notifications we'll likely need 64-bit type for identifying event. But OTOH requirements there are unclear and I can imagine even userspace assigning the ID. In the worst case we could add info record for this persistent event id. So ok, let's do it as you suggest. Honza -- Jan Kara <jack@xxxxxxxx> SUSE Labs, CR
