From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) (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 197C01EB5F6; Tue, 22 Apr 2025 07:32:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.95.11.211 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745307150; cv=none; b=cQXYnRLy2uwAOzQU3Em4Wx5JQiO6H1j6Z3w1thoQj9qhJ3kjIvPwI+HZ+PvjfckoJlzRlQlaUQTaUD2YnxGLRqvbiZ73QB0s4yO3NaxVoSareKk2nYY7L4hKN5JOcllqqqdOqR50ze7t8GH9NA6FsqSLU3fyrXDymJ+jCX6I+WA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745307150; c=relaxed/simple; bh=Keqxor1ODBLPmVawW5vsbj3/9Z2VBK6VDWsYSbORC00=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=E/OWHgbjwX6015ma4TJHRG4iXwD28vIrqfbTa0RTThOjCXqnnypfqPxbYMSM8HWNzFZhEkOE9zG11nKL7ydX3/ZYf/4iLLpSS/Vy8aOxKZJVEkR1c5Z3cWcQOqE1uEOGW9paN5tdxU5btC+ImZ9cshZBoHid/aZxnyNjLDXF9NI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=lst.de; spf=pass smtp.mailfrom=lst.de; arc=none smtp.client-ip=213.95.11.211 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=lst.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=lst.de Received: by verein.lst.de (Postfix, from userid 2407) id 0CE9D68AA6; Tue, 22 Apr 2025 09:32:22 +0200 (CEST) Date: Tue, 22 Apr 2025 09:32:21 +0200 From: Christoph Hellwig To: Leon Romanovsky Cc: Christoph Hellwig , Marek Szyprowski , Jens Axboe , Keith Busch , Jake Edge , Jonathan Corbet , Jason Gunthorpe , Zhu Yanjun , Robin Murphy , Joerg Roedel , Will Deacon , Sagi Grimberg , Bjorn Helgaas , Logan Gunthorpe , 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, linux-pci@vger.kernel.org, kvm@vger.kernel.org, linux-mm@kvack.org, Niklas Schnelle , Chuck Lever , Luis Chamberlain , Matthew Wilcox , Dan Williams , Kanchan Joshi , Chaitanya Kulkarni Subject: Re: [PATCH v8 23/24] nvme-pci: convert to blk_rq_dma_map Message-ID: <20250422073221.GA31688@lst.de> References: <20250422050050.GB28077@lst.de> <20250422072606.GC48485@unreal> Precedence: bulk X-Mailing-List: linux-doc@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: <20250422072606.GC48485@unreal> User-Agent: Mutt/1.5.17 (2007-11-01) On Tue, Apr 22, 2025 at 10:26:06AM +0300, Leon Romanovsky wrote: > On Tue, Apr 22, 2025 at 07:00:50AM +0200, Christoph Hellwig wrote: > > > + dma_len = min_t(u32, length, NVME_CTRL_PAGE_SIZE - (dma_addr & (NVME_CTRL_PAGE_SIZE - 1))); > > > > And overly long line slipped in here during one of the rebases. > > > > > + /* > > > + * We are in this mode as IOVA path wasn't taken and DMA length > > > + * is morethan two sectors. In such case, mapping was perfoormed > > > + * per-NVME_CTRL_PAGE_SIZE, so unmap accordingly. > > > + */ > > > > Where does this comment come from? Lots of spelling errors, and I > > also don't understand what it is talking about as setors are entirely > > irrelevant here. > > I'm trying to say when this do {} while is taken and sector is a wrong > word to describe NVME_CTRL_PAGE_SIZE. Let's remove this comment. Yes, I'd say drop it. > > With the addition of metadata SGL support this also needs to check > > NVME_CMD_SGL_METASEG. > > > > The commit message should also really mentioned that someone > > significantly altered the patch for merging with latest upstream, > > as I as the nominal author can't recognize some of that code. > > Someone :), I thought that adding my SOB is enough. Well, it also has Chaitanya's, so it must have passed through both of you at least. Usually you want to add a little line explaining what you changed for non-trivial changes when changing it. > if (!blk_rq_dma_unmap(req, dev->dev, &iod->dma_meta_state, > iod->total_meta_len)) { > - if (entries == 1) { > + if (iod->cmd.common.flags & NVME_CMD_SGL_METASEG) { > + unsigned int i; > + > + for (i = 0; i < entries; i++) > + dma_unmap_page(dev->dev, > + le64_to_cpu(sg_list[i].addr), > + le32_to_cpu(sg_list[i].length), dir); > + } else { > dma_unmap_page(dev->dev, iod->meta_dma, > - rq_integrity_vec(req).bv_len, > - rq_dma_dir(req)); > + rq_integrity_vec(req).bv_len, dir); > return; It would be nice if we could share a bit of code with the data mapping, but I'm not sure that's possible. I'll try to look into it and review things more carefully once I've reduced my backlog.