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	Thu, 09 Jul 2026 06:22:05 +0000
Date: Wed, 8 Jul 2026 23:22:05 -0700
From: Christoph Hellwig <hch@infradead.org>
To: Pranjal Shrivastava <praan@google.com>
Cc: Christoph Hellwig <hch@infradead.org>,
	Matthew Wilcox <willy@infradead.org>,
	Trond Myklebust <trondmy@kernel.org>, linux-nfs@vger.kernel.org,
	linux-kernel@vger.kernel.org, Anna Schumaker <anna@kernel.org>,
	Shivaji Kant <shivajikant@google.com>, linux-mm@kvack.org,
	linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH v2 6/7] nfs: Optimize direct I/O to use folios for
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On Thu, Jul 09, 2026 at 06:19:12AM +0000, Pranjal Shrivastava wrote:
> On Wed, Jul 08, 2026 at 11:47:27AM +0000, Pranjal Shrivastava wrote:
> > On Wed, Jul 08, 2026 at 12:48:56AM -0700, Christoph Hellwig wrote:
> > > On Tue, Jul 07, 2026 at 12:08:27PM +0000, Pranjal Shrivastava wrote:
> > > > Ack. I see! Thanks!
> > > > 
> > > > Regarding the page_folio impasse, how do you suggest we proceed? Should
> > > > I expose and use get_contig_folio_len() from bvec? Or should I move the
> > > > NFS helper into the iov_iter lib? (or both).
> > > 
> > > Sounds like the best way forward for now.
> > 
> > Ack. I'll reuse get_contig_folio len and move the nfs extractor to
> > iov_iter for v3.
> > 
> 
> On a second thought, I guess I'd try taking a stab at writing
> iov_iter_extract_folios and handle the vmalloc / slab cases for kvecs. 
> I believe that would be the right way to go, unless I'm missing
> something obvious? Can I take a stab at it in the next version?

That does sound good, but it might get you into some longer discussions.