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Date: Wed, 1 May 2024 00:55:48 -0700
From: Christoph Hellwig <hch@infradead.org>
To: David Wei <dw@davidwei.uk>
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Subject: Re: [RFC PATCH net-next v8 07/14] page_pool: devmem support
Message-ID: <ZjH1hO8qJgOqNKub@infradead.org>
References: <20240403002053.2376017-1-almasrymina@google.com>
 <20240403002053.2376017-8-almasrymina@google.com>
 <8357256a-f0e9-4640-8fec-23341fc607db@davidwei.uk>
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In-Reply-To: <8357256a-f0e9-4640-8fec-23341fc607db@davidwei.uk>

On Fri, Apr 26, 2024 at 05:17:52PM -0700, David Wei wrote:
> On 2024-04-02 5:20 pm, Mina Almasry wrote:
> > @@ -69,20 +106,26 @@ net_iov_binding(const struct net_iov *niov)
> >   */
> >  typedef unsigned long __bitwise netmem_ref;
> >  
> > +static inline bool netmem_is_net_iov(const netmem_ref netmem)
> > +{
> > +#if defined(CONFIG_PAGE_POOL) && defined(CONFIG_DMA_SHARED_BUFFER)
> 
> I am guessing you added this to try and speed up the fast path? It's
> overly restrictive for us since we do not need dmabuf necessarily. I
> spent a bit too much time wondering why things aren't working only to
> find this :(

So what else do you need?  I was assured last round that nothing but
dmabuf and potentially the huge page case (that really just is the page
provider) would get added.

> 
---end quoted text---