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 B5F587BB01; Tue, 30 Apr 2024 08:25:43 +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=1714465543; cv=none; b=WuyTeJ2eduFCx8gMPLofZrtmEumoR4If5IaDER0vCQm5eQX7gmkrlZWIwnIZLqJAbjmMKu6pdDBD3WJ/wTFKVZTf7YaAI8FPEt6a7q4a8eQ6G4bxCTklWBWPwvurnjXLtcK/JrihhLcIlglSx1iMZg/GuZ58cCIcS0KJ/+W87kw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714465543; c=relaxed/simple; bh=Y/sjR08e/Huau+7cIoWgrNdMy6qgZ4syIBJ/vQzG5CY=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=gsQY0wXM8/YjjpFTbz6ES011M+v44R2KaE/sQ0ksXYtON+yyXcoErTV8PMFRTB17PJF2jYemjpQRgHoJIqmTSAbVvDuMFbkAj3PjRMr6ehZzlXT7L1j2C/Uet6g0BaMEO4S4vA/MDfPQ2whujK+Sxq76SBNajgrfPjFXGlVwvKo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=GYiA8rgX; 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="GYiA8rgX" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EA702C2BBFC; Tue, 30 Apr 2024 08:25:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1714465543; bh=Y/sjR08e/Huau+7cIoWgrNdMy6qgZ4syIBJ/vQzG5CY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=GYiA8rgXJV4+2zkPPV1eNSN3QK38TuQYFcU9knAy/f8HyMk4rJ0M1YdowO02l1100 5TBiga/Xu+GojvGaEsBpTQbC8XdB2EwikYuU+0dzJsmI4jWyVUxk4ygys+aItzPycs ChUkPBT+jc67axR8ECZIlECW9DlPG1938IptIzufZ/v55B/C35YdNHxVzH3X0ACcDx 0L7ds01EEW8jrwTgaGBEN2fiEQyJ0OEhEcH0yOuXbVaGOglsyDqvN4OIERglD8eYLC wlbxamAddIQ+5tRwnrDmrbx+H2EAo2PDyvWnadEhRtNrg1NtYIAWVPvESDh6gNPFrG E1MMzPCbva6+g== Date: Tue, 30 Apr 2024 09:25:38 +0100 From: Keith Busch To: Christoph Hellwig Cc: Kanchan Joshi , axboe@kernel.dk, martin.petersen@oracle.com, brauner@kernel.org, asml.silence@gmail.com, dw@davidwei.uk, io-uring@vger.kernel.org, linux-nvme@lists.infradead.org, linux-block@vger.kernel.org, gost.dev@samsung.com, Anuj Gupta Subject: Re: [PATCH 02/10] block: copy bip_max_vcnt vecs instead of bip_vcnt during clone Message-ID: References: <20240425183943.6319-1-joshi.k@samsung.com> <20240425183943.6319-3-joshi.k@samsung.com> <20240427070331.GB3873@lst.de> <73cc82c3-fbf6-ea3e-94ec-3bdce55af541@samsung.com> <20240429170728.GA31337@lst.de> Precedence: bulk X-Mailing-List: io-uring@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: <20240429170728.GA31337@lst.de> On Mon, Apr 29, 2024 at 07:07:29PM +0200, Christoph Hellwig wrote: > On Mon, Apr 29, 2024 at 01:04:12PM +0100, Keith Busch wrote: > > An earlier version added a field in the bip to point to the original > > bvec from the user address. That extra field wouldn't be used in the far > > majority of cases, so moving the user bvec to the end of the existing > > bip_vec is a spatial optimization. The code may look a little more > > confusing that way, but I think it's better than making the bip bigger. > > I think we need to do something like that - just hiding the bounce > buffer is not really maintainable once we get multiple levels of stacking > and other creative bio cloning. Not sure I follow that. From patches 2-4 here, I think that pretty much covers it. It's just missing a good code comment, but the implementation side looks complete for any amount of stacking and splitting.