On Fri, Nov 22, 2024 at 05:15:47PM +0100, Christoph Hellwig wrote: > On Fri, Nov 22, 2024 at 01:53:42PM +0100, Jan Kara wrote: > > Here I'm not so sure. Firstly, since you are an owner this doesn't add any > > additional practical restriction. Secondly, you are not changing anything > > on disk, just IO hints in memory... Thirdly, we generally don't require > > writeable fd even to do file attribute changes (like with fchmod, fchown, > > etc.). So although the check makes some sense, it seems to be mostly > > inconsistent with how we treat similar stuff. > > As I said I'm not quite convince either, so just doing the first one > is probably fine. We do require FMODE_WRITE to do a dedupe, which isn't exactly the same but is similar in concept (we're not changing the content of the file; we're changing how it's laid out on storage). So I think it's reasonable to require FMODE_WRITE to set the write hints.
