From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id AA08F26CE3F; Fri, 16 Jan 2026 21:14:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768598059; cv=none; b=HETRd7/d1RW4cdQbcWy5gLdB4j/MEKWubpY5EbL6HURQ+FNOUEEUwQpkMAOgPVpzfPlchMVrtxWfdKYwAPwkvZprhXUBjRfx6wS0MmMCcZ/lUtextiNlpi2WdyKDDmQ7xrC9nBzAsvV/QJ2D/WBEKH8zXpPIqlvji/7zF7hPOZo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768598059; c=relaxed/simple; bh=sijbnpL9XBVDCYz165hl+AewDEG+1x0EOeW8l0BatnA=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=eq6Kh+pmBYVpCC/DzC2jI6jwcWKMCtWq8MZ8HFO3H94UxxhdIIFj7tDHRzlPc9NmX9894EzXVIZkh/dPjVogassCv7tUYkPJYxUx3M9kTaaZRZdDgGSl0qK5TjUwKRkKencJY9Jap1wqPIDOCZr9MUsxdSG2CJ2U6q+/PqC+OtA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=EkpNc/eA; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="EkpNc/eA" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8B40BC116C6; Fri, 16 Jan 2026 21:14:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1768598059; bh=sijbnpL9XBVDCYz165hl+AewDEG+1x0EOeW8l0BatnA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=EkpNc/eA2qeSTt0JUpLxtYNfQzu0om0ORxToocorSmE9cFHyNBx10xdL5+5n7Kb/2 CLfRnHiS72J/MJyWFt1bT5snUv4OQ32htWRksLuolRKYzrIwa67vJJH5sIUmGyoOsJ Lx6VJ+R1J1JwK2fpeDXNLjwN6GTYUt35ZSSZxc0lC5f2Fbpu2/YDXCLVi2UN6xL8j3 NGQywU9Ub/FONNr+Kp8Bu/2aAVzjGOjRGtbULP1T7pcnXkcoZTyM0xiumnZax1l+go 1hT1l5z3cAF/elONohxoz6B101FsaLJ7FNEZa1fUPQv9en4IYDXaqyNfZIMKMVI4mw VXDB5ZlJmGl4A== Date: Fri, 16 Jan 2026 23:14:13 +0200 From: Leon Romanovsky To: Chuck Lever Cc: Christoph Hellwig , Jason Gunthorpe , linux-rdma@vger.kernel.org, linux-nfs@vger.kernel.org, NeilBrown , Jeff Layton , Olga Kornievskaia , Dai Ngo , Tom Talpey , Chuck Lever Subject: Re: [PATCH v1 1/4] RDMA/core: add bio_vec based RDMA read/write API Message-ID: <20260116211413.GH14359@unreal> References: <20260114143948.3946615-1-cel@kernel.org> <20260114143948.3946615-2-cel@kernel.org> <20260115155334.GB14083@lst.de> <20260116113310.GF14359@unreal> <20260116145206.GB16842@lst.de> <19c34c0c-5391-477b-892c-00ab124e543b@app.fastmail.com> Precedence: bulk X-Mailing-List: linux-rdma@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <19c34c0c-5391-477b-892c-00ab124e543b@app.fastmail.com> On Fri, Jan 16, 2026 at 09:57:57AM -0500, Chuck Lever wrote: > > > On Fri, Jan 16, 2026, at 9:52 AM, Christoph Hellwig wrote: > > On Fri, Jan 16, 2026 at 01:33:10PM +0200, Leon Romanovsky wrote: > >> > Much of this seems to duplicate rdma_rw_init_map_wrs. I wonder if > >> > having a low-level helper that gets either a scatterlist or bvec array > >> > (or bvec_iter) and just has different inner loops for them would > >> > make more sense? If not we'll just need to migrate everyone off > >> > the scatterlist version ASAP :) > >> > >> I had short offline discussion with Jason about this series and both of > >> us would be more than happy to get rid of "scatterlist version". > > > > nvmet_rdma_rw_ctx_init is used by isert, srpt, nvmet, ksmbd and > > the sunrpc server side. I don't think any of them should be > > super complicated to work, but it will need a fair amount of testing > > resources. > > My preference is to keep the scope of this series narrow -- > introduce the new API, and add one consumer for it. The other > conversions can then each be done by domain experts as they > have time. Of course, I'm only outlining the direction in which the RDMA subsystem is expected to evolve. > > I have no strong feeling for or against eventually removing > SGL support entirely from rw.c. > > -- > Chuck Lever