From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 76868C4345F for ; Sun, 5 May 2024 13:23:24 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 750446B007B; Sun, 5 May 2024 09:23:23 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 6D8716B0082; Sun, 5 May 2024 09:23:23 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 551E66B0085; Sun, 5 May 2024 09:23:23 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id 337D26B007B for ; Sun, 5 May 2024 09:23:23 -0400 (EDT) Received: from smtpin01.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id A2A661203CA for ; Sun, 5 May 2024 13:23:22 +0000 (UTC) X-FDA: 82084408644.01.C57698E Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf06.hostedemail.com (Postfix) with ESMTP id E949B180003 for ; Sun, 5 May 2024 13:23:20 +0000 (UTC) Authentication-Results: imf06.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=N5GHCqgu; dmarc=pass (policy=none) header.from=kernel.org; spf=pass (imf06.hostedemail.com: domain of leon@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=leon@kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1714915401; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=mKB6YLSNJL854QSVR6Ylw1i1qlJgNfvLSDvIS/fCb8M=; b=zayIUHF/qqSndKfBEAWzoCCCuX7hWfeP+Msnp09Kdnqndk27Ew4lxyjYlxigRRwRt4vRfp jqMk7KaTn2gp7TT+jRrfsF7zp1/ac5P90voBx4BpMl1t+Uj8qe1X+qicX536eEpOqxSdyF 9ENKxaVUEJDflsvBx3dMYObMwcW3Tzk= ARC-Authentication-Results: i=1; imf06.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=N5GHCqgu; dmarc=pass (policy=none) header.from=kernel.org; spf=pass (imf06.hostedemail.com: domain of leon@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=leon@kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1714915401; a=rsa-sha256; cv=none; b=aFcMJ2M0X4cl7jkxmUZOE7CAcfSgxgzRhYStoY00PJyIgrfeUZhj9b5+zTtrRjyldvHgxn 3IHKTi0cgaqm0tsOiqP4ljDyWcmPJ8D+bXFJ1okUX3cdDoUcsF6H+u7gPmzvXhM5ieA0lw GDSfQ0LirR2s34/AC++t+TxUfDn2pf4= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id 96D1560C64; Sun, 5 May 2024 13:23:19 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5357AC113CC; Sun, 5 May 2024 13:23:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1714915399; bh=jjLgkhsN4WjaKTyfGnNOYYnBmrIQeAxiqhWYRqvmHnw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=N5GHCqguzvr4zXSvt+GZwExP+D4+ViMFS5ymKVV8WJY+Di3qvsEp58G9bzM0BAvHF stRLiuNs0tAjzhnbTK/8wL+10XQCHTZHBZmaoU+SwNNRsdc3zzqE5WaLVDQBWFhIvC raDXBTYUnDUM4UtQUw45YXqktzY6vnT/akcSLM5mL4wzzUFTgqPDcpICsM95p6XfvX O4u+h30wrlLfM0mEibSSqU02f0NAECeoPPcaFHr27oYznJKIN+ZSxxnHDgLyJZSjxm mLLAI46IamcYUju5EL6BBITjFGKFCEyP7IgsxkDT4H6bFHDEu7oWOLwbNzfk28/Nrq GrAQIMAtf2uAg== Date: Sun, 5 May 2024 16:23:14 +0300 From: Leon Romanovsky To: Zhu Yanjun Cc: Christoph Hellwig , Robin Murphy , Marek Szyprowski , Joerg Roedel , Will Deacon , Jason Gunthorpe , Chaitanya Kulkarni , Chaitanya Kulkarni , Jonathan Corbet , Jens Axboe , Keith Busch , Sagi Grimberg , Yishai Hadas , Shameer Kolothum , Kevin Tian , Alex Williamson , =?iso-8859-1?B?Suly9G1l?= Glisse , Andrew Morton , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, linux-rdma@vger.kernel.org, iommu@lists.linux.dev, linux-nvme@lists.infradead.org, kvm@vger.kernel.org, linux-mm@kvack.org, Bart Van Assche , Damien Le Moal , Amir Goldstein , "josef@toxicpanda.com" , "Martin K. Petersen" , "daniel@iogearbox.net" , Dan Williams , "jack@suse.com" Subject: Re: [RFC RESEND 16/16] nvme-pci: use blk_rq_dma_map() for NVMe SGL Message-ID: <20240505132314.GC68202@unreal> References: <016fc02cbfa9be3c156a6f74df38def1e09c08f1.1709635535.git.leon@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Server: rspam01 X-Stat-Signature: kfuua8barmpao7d7rpfgfpro3qa4y6tk X-Rspam-User: X-Rspamd-Queue-Id: E949B180003 X-HE-Tag: 1714915400-641002 X-HE-Meta: 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 o6coQUHE +nPduRguW3UrUDGkapwHV+KQ6bBrf2tBJAtPinZhNFHlqnuEeUYy0dasZAYV4xfJM+gw0owgyN7Ows+RSsctF77tAfr0KEnnNoAF6vM766r5wibEaYM/ZThEaTJhQBJeWk85cJaO0RtwY50dqWYhBo+4wqiUx+IpO6pSoKpdfM7eLLj/wXGpbQcrVCbNSm3MlowSIxEd5aoUe3O9WqmQXlE/A5flaGBQ+sYEUiPjwL9c/dVbJlU2CvS6l4Wk2YBFnYtToTnmqNQnY66g/tEfkWQJdeOkhNoTV+EOk9qLSmBkIO5Q= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, May 03, 2024 at 04:41:21PM +0200, Zhu Yanjun wrote: > On 05.03.24 12:18, Leon Romanovsky wrote: > > From: Chaitanya Kulkarni <...> > > This is an RFC to demonstrate the newly added DMA APIs can be used to > > map/unmap bvecs without the use of sg list, hence I've modified the pci > > code to only handle SGLs for now. Once we have some agreement on the > > structure of new DMA API I'll add support for PRPs along with all the > > optimization that I've removed from the code for this RFC for NVMe SGLs > > and PRPs. > > <...> > > diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c > > index e6267a6aa380..140939228409 100644 > > --- a/drivers/nvme/host/pci.c > > +++ b/drivers/nvme/host/pci.c > > @@ -236,7 +236,9 @@ struct nvme_iod { > > unsigned int dma_len; /* length of single DMA segment mapping */ > > dma_addr_t first_dma; > > dma_addr_t meta_dma; > > - struct sg_table sgt; > > + struct dma_iova_attrs iova; > > + dma_addr_t dma_link_address[128]; > > Why the length of this array is 128? Can we increase this length of the > array? It is combination of two things: * Good enough value for this nvme RFC to pass simple test, which Chaitanya did. * Output of various NVME_CTRL_* defines Thanks