From: Jeff Layton > Sent: 18 September 2023 15:30 .... > A bit tangential to this discussion, but one thing we could consider is > adding something like a mnt_change_cookie field that increments on any > significant changes on the mount: i.e. remounts with new options, > changes to parentage or propagation, etc. > > That might make it more palatable to do something with separate syscalls > for the string-based fields. You could do: > > statmnt(...); > getmntattr(mnt, "mnt.fstype", ...); > statmnt(...); > > ...and then if the mnt_change_cookie hasn't changed, you know that the > string option was stable during that window. That would also help with the problem of the mount options being changed while processing a page fault on the user buffer. Of, with a call to just get the cookie, could find that nothing has changed so there is no point looking again. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)
