Re: [PATCH v4 0/9] Update to zstd-1.4.6

[Chris Mason]

On 2 Oct 2020, at 2:54, Christoph Hellwig wrote:

> On Wed, Sep 30, 2020 at 08:05:45PM +0000, Nick Terrell wrote:
> > > On Sep 29, 2020, at 11:53 PM, Christoph Hellwig <hch@xxxxxxxxxxxxx> 
> > > wrote:
> > >
> > > As you keep resend this I keep retelling you that should not do it.
> > > Please provide a proper Linux API, and switch to that.  Versioned 
> > > APIs
> > > have absolutely no business in the Linux kernel.
> >
> > The API is not versioned. We provide a stable ABI for a large section 
> > of our API,
> > and the parts that aren???t ABI stable don???t change in semantics, 
> > and undergo long
> > deprecation periods before being removed.
> >
> > The change of callers is a one-time change to transition from the 
> > existing API
> > in the kernel, which was never upstream's API, to upstream's API.
>
> Again, please transition it to a sane kernel API.  We don't have an
> "upstream" in this case.

The upstream is the zstd project where all this code originates, and 
where the active development takes place.  As Eric Biggers pointed out, 
it also receives a lot of Q/A separate from the kernel.  I think we gain 
a great deal by leveraging the testing and documentation of the zstd 
project in the kernel interfaces we use.

We lose some consistency with the kernel coding style, but we gain the 
ability to search for docs, issues, and fixes directly against the zstd 
project and git repo.

-chris