Re: [PATCH 1/2] NFSD: Fix duplicate fsnotify access events for iterator READs

[Amir Goldstein]

On Sun, Aug 23, 2026 at 6:21 PM Chuck Lever <cel@xxxxxxxxxx> wrote:
>
>
>
> On Sat, Aug 22, 2026, at 6:21 AM, Amir Goldstein wrote:
> > (1) In this series
> > https://lore.kernel.org/linux-fsdevel/20231122122715.2561213-1-amir73il@xxxxxxxxx/
> > we intentionally moved the permission hook outside
> > of the splice iterators because we wanted to avoid calling them
> > with freeze protection held and also there were some duplicate calls
> > for this work.
> >
> > At this point in time, the fsnotify_{access,modify} post hooks are
> > usually called
> > from the same context as the matching permission/security hooks.
> > It doesn't have to be this way, but it's a good mental model IMO.
> >
> > (2) emitting many READ events from an iterator instead of one event for
> > the user's READ request is more noisy and serves no purpose to users.
> > In most cases (but not always) those events could be merged, but at the
> > cost of futile CPU cycles.
> >
> > From a quick inspection of the code, it looks like:
> > - fsnotify_access() is missing in vfs_splice_read()
> > - the naming convention for splice_ do_splice_ vfs_splice_ is a horror
> > - we could make the low level splice_direct_to_actor() static and possibly
> >   rename it to splice_direct_to_actor_sd() or something
> > - we could export vfs_splice_direct_to_actor() for nfsd which wraps
> >   splice_direct_to_actor() with permission hook and fsnotify_access
>
> IIUC this last bullet seems like clean layering to me. Do
> you want to propose a patch or shall I?

Be my guest.
Maybe Ameer will want to post it for v2.

Thanks,
Amir.