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 X-Spam-Level: X-Spam-Status: No, score=-2.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_MUTT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4BF1FC43613 for ; Mon, 24 Jun 2019 18:54:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1F79920663 for ; Mon, 24 Jun 2019 18:54:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=ziepe.ca header.i=@ziepe.ca header.b="bssP7nVt" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729619AbfFXSyu (ORCPT ); Mon, 24 Jun 2019 14:54:50 -0400 Received: from mail-wm1-f68.google.com ([209.85.128.68]:37082 "EHLO mail-wm1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729595AbfFXSyu (ORCPT ); Mon, 24 Jun 2019 14:54:50 -0400 Received: by mail-wm1-f68.google.com with SMTP id f17so394594wme.2 for ; Mon, 24 Jun 2019 11:54:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ziepe.ca; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=2VLB62LTLlXO8oWMzmxndKFmxYDQNRrl1nYzZ7fiBH8=; b=bssP7nVtbxic8x1W+7aINGmVwUOYnfJSdJihHr+XXest3Vx9i0deL1LOz0fug7R1U1 B5g5IL/YBGy8xioHik2tNV6c6asgwNQLrq+uBuFoxRMgZJ4BuztaJWrkpPSpqVsKILZx 14viaNCjBFFfPcy4wbxl2lhjSG22PDgW5GgEPY+aiVW57k23uu6GJEjQYvC/FgVfHEUM 7d3P9SFXDAUtN220jCpceeo0OnTuWEohYBulBbQvXmpACGPIxLabY5EMrRWaAaowQaS4 rSCmwjE/WHV4DGUGkvibovageI+23aZgeutKLX3qZ1Fp8lrfuajpCPGxlls7Z8yyNbcA ILfA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=2VLB62LTLlXO8oWMzmxndKFmxYDQNRrl1nYzZ7fiBH8=; b=W37oFW4a8AvpouVYS+4hWMmpTqyFPv3itfnJwgcPoSO+n/M844daCY1VoqPSsPy6Eq MIljP2rVDifuGyW1di03A1ldj+0JV5ZKSjX0lk4yJ3TqpwE63X/4QGneeL0cbjrsEbug lyeUYXsEwTXEXNkn9c7cR+IaO5a+FPh1JafOtZzPu2eIXpxoB0QhvcZnuhw7tc9Z2e/S COzsCJeHwFMnP5c6UmshiIfjmpvLHfLy1XwENb5AYt3Xaedy8ZhXFgWWl98HPU3s+kj8 SZsSsspJ0Q5Ck4DiM7gGCczN3PDn0QA1f6MAJmNqZuFKwI2WcUQCVZjYDOSolFg3vLP1 XigQ== X-Gm-Message-State: APjAAAUkiBVhznQ098huxGNeNTRU0A0lepmUFqX1Y14c3xurI38gg9o1 D9WQ+T8qchXLVQKG0Ti3MTWo6Q== X-Google-Smtp-Source: APXvYqwuzff7/kg/rNAW2pQFDbje1NhrbmshAeZpBjzb6O9dqiGhfTGm1OhmaQBXRqL6CYA5mJ8psQ== X-Received: by 2002:a7b:c94a:: with SMTP id i10mr16384528wml.97.1561402487618; Mon, 24 Jun 2019 11:54:47 -0700 (PDT) Received: from ziepe.ca ([66.187.232.66]) by smtp.gmail.com with ESMTPSA id y2sm10324854wrl.4.2019.06.24.11.54.46 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Mon, 24 Jun 2019 11:54:46 -0700 (PDT) Received: from jgg by jggl.ziepe.ca with local (Exim 4.90_1) (envelope-from ) id 1hfU72-0006ZX-QC; Mon, 24 Jun 2019 15:54:44 -0300 Date: Mon, 24 Jun 2019 15:54:44 -0300 From: Jason Gunthorpe To: Logan Gunthorpe Cc: Christoph Hellwig , Dan Williams , Linux Kernel Mailing List , linux-block@vger.kernel.org, linux-nvme@lists.infradead.org, linux-pci@vger.kernel.org, linux-rdma , Jens Axboe , Bjorn Helgaas , Sagi Grimberg , Keith Busch , Stephen Bates Subject: Re: [RFC PATCH 00/28] Removing struct page from P2PDMA Message-ID: <20190624185444.GD8268@ziepe.ca> References: <20190620161240.22738-1-logang@deltatee.com> <20190620193353.GF19891@ziepe.ca> <20190624073126.GB3954@lst.de> <20190624134641.GA8268@ziepe.ca> <20190624135024.GA11248@lst.de> <20190624135550.GB8268@ziepe.ca> <7210ba39-c923-79ca-57bb-7cf9afe21d54@deltatee.com> <20190624181632.GC8268@ziepe.ca> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Mon, Jun 24, 2019 at 12:28:33PM -0600, Logan Gunthorpe wrote: > > Sounded like this series does generate the dma_addr for the correct > > device.. > > This series doesn't generate any DMA addresses with dma_map(). The > current p2pdma code ensures everything is behind the same root port and > only uses the pci bus address. This is valid and correct, but yes it's > something to expand upon. I think if you do this it still has to be presented as the same API like dma_map that takes in the target device * and produces the device specific dma_addr_t Otherwise this whole thing is confusing and looks like *all* of it can only work under the switch assumption Jason