On Fri, Oct 19, 2018 at 8:44 PM Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote: > > On Fri, Oct 19, 2018 at 07:14:23PM +0300, Amir Goldstein wrote: > > > On Fri, Oct 19, 2018 at 6:30 PM Olga Kornievskaia > > > <olga.kornievskaia@xxxxxxxxx> wrote: > > > > Allow copy_file_range to copy between different superblocks but only > > > > of the same file system types. This feature was of interest to CIFS > > > > as well as NFS. > > > > Sorry, you meant to allow cross sb copy from client, so you do want > > to change user facing behavior. > > For that you need to declare a flag to opt in for the new behavior > > and document it. > > Please keep linux-api CC-ed when posting the flag. > > Referencing a draft for man page is recommended. > > Huh? We're allowed to make things work that used to fail. There's no > need to add a flag that the user must set. OK, you are right. Maybe this case doesn't call for an opt-in flag. I'll let other people weight in. I should note that the behavior of copy_file_range() has already changed silently to try to clone_file_range() first and that went quietly... Thanks, Amir.