Re: [PATCH 01/21] procfs: kill ->proc_dops

[Al Viro <viro@zeniv.linux.org.uk>]

On Wed, Feb 26, 2025 at 10:30:21AM +1100, NeilBrown wrote:
> On Wed, 26 Feb 2025, Jan Kara wrote:
> > On Mon 24-02-25 21:20:31, Al Viro wrote:
> > > It has two possible values - one for "forced lookup" entries, another
> > > for the normal ones.  We'd be better off with that as an explicit
> > > flag anyway and in addition to that it opens some fun possibilities
> > > with ->d_op and ->d_flags handling.
> > > 
> > > Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
> > 
> > FWIW I went through the patches and I like them. They look mostly
> > straightforward enough to me and as good simplifications.
> > 
> 
> Ditto.  Nice clean-up
> It might be good to document s_d_flags and particularly the value of
> setting DCACHE_DONTCACHE.  That flag is documented in the list of
> DCACHE_ flags, but making the connection that it can usefully be put in
> s_d_flags might be a step to far for many.

Probably...  The thing is, I'm resurrecting the DCACHE_PERSISTENT
patchset (aka tree-in-dcache stuff) and that will have non-trivial
interplay there.  But you are right - it's probably worth documenting
that thing in this series.

Re documentation - I'll be posting bits and pieces of dcache
docs/audit/proofs of correctness over the next few weeks; at some
point we'll need to collect that into a single text, but at the
moment what I've got is too disjoint for that.  OTOH, we could
start a WIP variant in D/f/<something> and have it augmented as
we go...  Not sure.