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=-7.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 C34B9C10DCE for ; Tue, 24 Mar 2020 05:49:15 +0000 (UTC) Received: from silver.osuosl.org (smtp3.osuosl.org [140.211.166.136]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 5D1E020724 for ; Tue, 24 Mar 2020 05:49:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=ozlabs-ru.20150623.gappssmtp.com header.i=@ozlabs-ru.20150623.gappssmtp.com header.b="Q+tWaHn1" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5D1E020724 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ozlabs.ru Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by silver.osuosl.org (Postfix) with ESMTP id 2AF49204AB; Tue, 24 Mar 2020 05:49:15 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from silver.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 9IPR+L+7B9OM; Tue, 24 Mar 2020 05:49:14 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by silver.osuosl.org (Postfix) with ESMTP id 146542046F; Tue, 24 Mar 2020 05:49:14 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id EC2DBC1AE2; Tue, 24 Mar 2020 05:49:13 +0000 (UTC) Received: from fraxinus.osuosl.org (smtp4.osuosl.org [140.211.166.137]) by lists.linuxfoundation.org (Postfix) with ESMTP id 3841EC0177 for ; Tue, 24 Mar 2020 05:49:12 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by fraxinus.osuosl.org (Postfix) with ESMTP id 2C68E844D3 for ; Tue, 24 Mar 2020 05:49:12 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from fraxinus.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id dM-Iyz3xh86V for ; Tue, 24 Mar 2020 05:49:10 +0000 (UTC) X-Greylist: delayed 00:47:17 by SQLgrey-1.7.6 Received: from mail-vk1-f195.google.com (mail-vk1-f195.google.com [209.85.221.195]) by fraxinus.osuosl.org (Postfix) with ESMTPS id 936D884495 for ; Tue, 24 Mar 2020 05:49:10 +0000 (UTC) Received: by mail-vk1-f195.google.com with SMTP id s139so4480576vka.13 for ; Mon, 23 Mar 2020 22:49:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ozlabs-ru.20150623.gappssmtp.com; s=20150623; h=subject:from:to:cc:references:autocrypt:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=ocy7e1KeETG7j3uo/d7wFUct0TjKed3FplbOKEqHuUU=; b=Q+tWaHn1r8jDF7IG+TJJbYdtXDaXlAzpopO1lNgcS2JtSahJ0aV5yRIhWOeli/UJNC EyzZwGG2D+kdYqijOGJOxFVq7cCu2wJF+dXPuKdcokVT5U2LFz0ScFSriIbYRoJ2518h 4tzYEVcFINB/7jwcCb/SaL7sixfIMoqECdQN9+vdGm5ezs/Ounsgouv9bpKuufz+43Sp pH9TryPxfoOUFPKBXbDxFM9s59g9JSq0DDQLl6rGMXQECULCdhq4pOM0oumxytR/SE4B cMFlVATqQthQAC484OYJHLUj4+vcgU/hWXKy8jSQWwSN5lrrwhf+4l56/YVXJV3Bqpx7 Qbsg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:from:to:cc:references:autocrypt :message-id:date:user-agent:mime-version:in-reply-to :content-language:content-transfer-encoding; bh=ocy7e1KeETG7j3uo/d7wFUct0TjKed3FplbOKEqHuUU=; b=K5rpbspVBUWsQtUtdSr4i18Vu3ZRhjn2UnKzzKokoVl2Gm7w1SdYSoPAbU03LVEoNN USJ8sF3wBfxRdEVtOAcWn/dKCTwjBZyAKiULuwgGWrjWmvKQzb53R3uVNE8GTpWYKoeR cve2eKNpMmLRml+RCqg5/+HbW+gPVQEkW2V297QZaefGU36r47zyvSCeGkPDopDzLQOo AuTHSUICo0Euk0Kh5imVH7Su0UWC4vOlUMpwFFaufMRaz0TqLUF0RP4fGSa5GQeYKjJ/ JxMv3RTb2XrUy216aGS21Pg7Vc5aYd6eE9lTw82YmIHh0K//64Uzso2TkM/gtITlHdnn mZOg== X-Gm-Message-State: ANhLgQ0X0oDgWL+x0lNwtvuR1dnbioV4GZ6N6WeBPqznWFE7Qyh6o+p7 9ZeC2HCa5nnK8+PviYavTq3xF4y60Ww= X-Google-Smtp-Source: ADFU+vs+nW/x1NavOeiZHD9rxw41LONWXbgDRtVmfaqm15LIuYpY5s1dvlRBHeTav5eMVQA69vpFgw== X-Received: by 2002:a17:902:b68b:: with SMTP id c11mr23925180pls.186.1585025739038; Mon, 23 Mar 2020 21:55:39 -0700 (PDT) Received: from [192.168.10.21] (ppp121-45-221-81.bras1.cbr2.internode.on.net. [121.45.221.81]) by smtp.gmail.com with ESMTPSA id o65sm8444662pfg.187.2020.03.23.21.55.35 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 23 Mar 2020 21:55:38 -0700 (PDT) Subject: Re: [PATCH 1/2] dma-mapping: add a dma_ops_bypass flag to struct device From: Alexey Kardashevskiy To: Christoph Hellwig References: <20200320141640.366360-1-hch@lst.de> <20200320141640.366360-2-hch@lst.de> <2f31d0dd-aa7e-8b76-c8a1-5759fda5afc9@ozlabs.ru> <20200323083705.GA31245@lst.de> <37ce1b7e-264d-292d-32b1-093b24b3525c@ozlabs.ru> <20200323172014.GA31269@lst.de> Autocrypt: addr=aik@ozlabs.ru; keydata= mQINBE+rT0sBEADFEI2UtPRsLLvnRf+tI9nA8T91+jDK3NLkqV+2DKHkTGPP5qzDZpRSH6mD EePO1JqpVuIow/wGud9xaPA5uvuVgRS1q7RU8otD+7VLDFzPRiRE4Jfr2CW89Ox6BF+q5ZPV /pS4v4G9eOrw1v09lEKHB9WtiBVhhxKK1LnUjPEH3ifkOkgW7jFfoYgTdtB3XaXVgYnNPDFo PTBYsJy+wr89XfyHr2Ev7BB3Xaf7qICXdBF8MEVY8t/UFsesg4wFWOuzCfqxFmKEaPDZlTuR tfLAeVpslNfWCi5ybPlowLx6KJqOsI9R2a9o4qRXWGP7IwiMRAC3iiPyk9cknt8ee6EUIxI6 t847eFaVKI/6WcxhszI0R6Cj+N4y+1rHfkGWYWupCiHwj9DjILW9iEAncVgQmkNPpUsZECLT WQzMuVSxjuXW4nJ6f4OFHqL2dU//qR+BM/eJ0TT3OnfLcPqfucGxubhT7n/CXUxEy+mvWwnm s9p4uqVpTfEuzQ0/bE6t7dZdPBua7eYox1AQnk8JQDwC3Rn9kZq2O7u5KuJP5MfludMmQevm pHYEMF4vZuIpWcOrrSctJfIIEyhDoDmR34bCXAZfNJ4p4H6TPqPh671uMQV82CfTxTrMhGFq 8WYU2AH86FrVQfWoH09z1WqhlOm/KZhAV5FndwVjQJs1MRXD8QARAQABtCRBbGV4ZXkgS2Fy ZGFzaGV2c2tpeSA8YWlrQG96bGFicy5ydT6JAjgEEwECACIFAk+rT0sCGwMGCwkIBwMCBhUI AgkKCwQWAgMBAh4BAheAAAoJEIYTPdgrwSC5fAIP/0wf/oSYaCq9PhO0UP9zLSEz66SSZUf7 AM9O1rau1lJpT8RoNa0hXFXIVbqPPKPZgorQV8SVmYRLr0oSmPnTiZC82x2dJGOR8x4E01gK TanY53J/Z6+CpYykqcIpOlGsytUTBA+AFOpdaFxnJ9a8p2wA586fhCZHVpV7W6EtUPH1SFTQ q5xvBmr3KkWGjz1FSLH4FeB70zP6uyuf/B2KPmdlPkyuoafl2UrU8LBADi/efc53PZUAREih sm3ch4AxaL4QIWOmlE93S+9nHZSRo9jgGXB1LzAiMRII3/2Leg7O4hBHZ9Nki8/fbDo5///+ kD4L7UNbSUM/ACWHhd4m1zkzTbyRzvL8NAVQ3rckLOmju7Eu9whiPueGMi5sihy9VQKHmEOx OMEhxLRQbzj4ypRLS9a+oxk1BMMu9cd/TccNy0uwx2UUjDQw/cXw2rRWTRCxoKmUsQ+eNWEd iYLW6TCfl9CfHlT6A7Zmeqx2DCeFafqEd69DqR9A8W5rx6LQcl0iOlkNqJxxbbW3ddDsLU/Y r4cY20++WwOhSNghhtrroP+gouTOIrNE/tvG16jHs8nrYBZuc02nfX1/gd8eguNfVX/ZTHiR gHBWe40xBKwBEK2UeqSpeVTohYWGBkcd64naGtK9qHdo1zY1P55lHEc5Uhlk743PgAnOi27Q ns5zuQINBE+rT0sBEACnV6GBSm+25ACT+XAE0t6HHAwDy+UKfPNaQBNTTt31GIk5aXb2Kl/p AgwZhQFEjZwDbl9D/f2GtmUHWKcCmWsYd5M/6Ljnbp0Ti5/xi6FyfqnO+G/wD2VhGcKBId1X Em/B5y1kZVbzcGVjgD3HiRTqE63UPld45bgK2XVbi2+x8lFvzuFq56E3ZsJZ+WrXpArQXib2 hzNFwQleq/KLBDOqTT7H+NpjPFR09Qzfa7wIU6pMNF2uFg5ihb+KatxgRDHg70+BzQfa6PPA o1xioKXW1eHeRGMmULM0Eweuvpc7/STD3K7EJ5bBq8svoXKuRxoWRkAp9Ll65KTUXgfS+c0x gkzJAn8aTG0z/oEJCKPJ08CtYQ5j7AgWJBIqG+PpYrEkhjzSn+DZ5Yl8r+JnZ2cJlYsUHAB9 jwBnWmLCR3gfop65q84zLXRQKWkASRhBp4JK3IS2Zz7Nd/Sqsowwh8x+3/IUxVEIMaVoUaxk Wt8kx40h3VrnLTFRQwQChm/TBtXqVFIuv7/Mhvvcq11xnzKjm2FCnTvCh6T2wJw3de6kYjCO 7wsaQ2y3i1Gkad45S0hzag/AuhQJbieowKecuI7WSeV8AOFVHmgfhKti8t4Ff758Z0tw5Fpc BFDngh6Lty9yR/fKrbkkp6ux1gJ2QncwK1v5kFks82Cgj+DSXK6GUQARAQABiQIfBBgBAgAJ BQJPq09LAhsMAAoJEIYTPdgrwSC5NYEP/2DmcEa7K9A+BT2+G5GXaaiFa098DeDrnjmRvumJ BhA1UdZRdfqICBADmKHlJjj2xYo387sZpS6ABbhrFxM6s37g/pGPvFUFn49C47SqkoGcbeDz Ha7JHyYUC+Tz1dpB8EQDh5xHMXj7t59mRDgsZ2uVBKtXj2ZkbizSHlyoeCfs1gZKQgQE8Ffc F8eWKoqAQtn3j4nE3RXbxzTJJfExjFB53vy2wV48fUBdyoXKwE85fiPglQ8bU++0XdOr9oyy j1llZlB9t3tKVv401JAdX8EN0++ETiOovQdzE1m+6ioDCtKEx84ObZJM0yGSEGEanrWjiwsa nzeK0pJQM9EwoEYi8TBGhHC9ksaAAQipSH7F2OHSYIlYtd91QoiemgclZcSgrxKSJhyFhmLr QEiEILTKn/pqJfhHU/7R7UtlDAmFMUp7ByywB4JLcyD10lTmrEJ0iyRRTVfDrfVP82aMBXgF tKQaCxcmLCaEtrSrYGzd1sSPwJne9ssfq0SE/LM1J7VdCjm6OWV33SwKrfd6rOtvOzgadrG6 3bgUVBw+bsXhWDd8tvuCXmdY4bnUblxF2B6GOwSY43v6suugBttIyW5Bl2tXSTwP+zQisOJo +dpVG2pRr39h+buHB3NY83NEPXm1kUOhduJUA17XUY6QQCAaN4sdwPqHq938S3EmtVhsuQIN BFq54uIBEACtPWrRdrvqfwQF+KMieDAMGdWKGSYSfoEGGJ+iNR8v255IyCMkty+yaHafvzpl PFtBQ/D7Fjv+PoHdFq1BnNTk8u2ngfbre9wd9MvTDsyP/TmpF0wyyTXhhtYvE267Av4X/BQT lT9IXKyAf1fP4BGYdTNgQZmAjrRsVUW0j6gFDrN0rq2J9emkGIPvt9rQt6xGzrd6aXonbg5V j6Uac1F42ESOZkIh5cN6cgnGdqAQb8CgLK92Yc8eiCVCH3cGowtzQ2m6U32qf30cBWmzfSH0 HeYmTP9+5L8qSTA9s3z0228vlaY0cFGcXjdodBeVbhqQYseMF9FXiEyRs28uHAJEyvVZwI49 CnAgVV/n1eZa5qOBpBL+ZSURm8Ii0vgfvGSijPGbvc32UAeAmBWISm7QOmc6sWa1tobCiVmY SNzj5MCNk8z4cddoKIc7Wt197+X/X5JPUF5nQRvg3SEHvfjkS4uEst9GwQBpsbQYH9MYWq2P PdxZ+xQE6v7cNB/pGGyXqKjYCm6v70JOzJFmheuUq0Ljnfhfs15DmZaLCGSMC0Amr+rtefpA y9FO5KaARgdhVjP2svc1F9KmTUGinSfuFm3quadGcQbJw+lJNYIfM7PMS9fftq6vCUBoGu3L j4xlgA/uQl/LPneu9mcvit8JqcWGS3fO+YeagUOon1TRqQARAQABiQRsBBgBCAAgFiEEZSrP ibrORRTHQ99dhhM92CvBILkFAlq54uICGwICQAkQhhM92CvBILnBdCAEGQEIAB0WIQQIhvWx rCU+BGX+nH3N7sq0YorTbQUCWrni4gAKCRDN7sq0YorTbVVSD/9V1xkVFyUCZfWlRuryBRZm S4GVaNtiV2nfUfcThQBfF0sSW/aFkLP6y+35wlOGJE65Riw1C2Ca9WQYk0xKvcZrmuYkK3DZ 0M9/Ikkj5/2v0vxz5Z5w/9+IaCrnk7pTnHZuZqOh23NeVZGBls/IDIvvLEjpD5UYicH0wxv+ X6cl1RoP2Kiyvenf0cS73O22qSEw0Qb9SId8wh0+ClWet2E7hkjWFkQfgJ3hujR/JtwDT/8h 3oCZFR0KuMPHRDsCepaqb/k7VSGTLBjVDOmr6/C9FHSjq0WrVB9LGOkdnr/xcISDZcMIpbRm EkIQ91LkT/HYIImL33ynPB0SmA+1TyMgOMZ4bakFCEn1vxB8Ir8qx5O0lHMOiWMJAp/PAZB2 r4XSSHNlXUaWUg1w3SG2CQKMFX7vzA31ZeEiWO8tj/c2ZjQmYjTLlfDK04WpOy1vTeP45LG2 wwtMA1pKvQ9UdbYbovz92oyZXHq81+k5Fj/YA1y2PI4MdHO4QobzgREoPGDkn6QlbJUBf4To pEbIGgW5LRPLuFlOPWHmIS/sdXDrllPc29aX2P7zdD/ivHABslHmt7vN3QY+hG0xgsCO1JG5 pLORF2N5XpM95zxkZqvYfC5tS/qhKyMcn1kC0fcRySVVeR3tUkU8/caCqxOqeMe2B6yTiU1P aNDq25qYFLeYxg67D/4w/P6BvNxNxk8hx6oQ10TOlnmeWp1q0cuutccblU3ryRFLDJSngTEu ZgnOt5dUFuOZxmMkqXGPHP1iOb+YDznHmC0FYZFG2KAc9pO0WuO7uT70lL6larTQrEneTDxQ CMQLP3qAJ/2aBH6SzHIQ7sfbsxy/63jAiHiT3cOaxAKsWkoV2HQpnmPOJ9u02TPjYmdpeIfa X2tXyeBixa3i/6dWJ4nIp3vGQicQkut1YBwR7dJq67/FCV3Mlj94jI0myHT5PIrCS2S8LtWX ikTJSxWUKmh7OP5mrqhwNe0ezgGiWxxvyNwThOHc5JvpzJLd32VDFilbxgu4Hhnf6LcgZJ2c Zd44XWqUu7FzVOYaSgIvTP0hNrBYm/E6M7yrLbs3JY74fGzPWGRbBUHTZXQEqQnZglXaVB5V ZhSFtHopZnBSCUSNDbB+QGy4B/E++Bb02IBTGl/JxmOwG+kZUnymsPvTtnNIeTLHxN/H/ae0 c7E5M+/NpslPCmYnDjs5qg0/3ihh6XuOGggZQOqrYPC3PnsNs3NxirwOkVPQgO6mXxpuifvJ DG9EMkK8IBXnLulqVk54kf7fE0jT/d8RTtJIA92GzsgdK2rpT1MBKKVffjRFGwN7nQVOzi4T XrB5p+6ML7Bd84xOEGsj/vdaXmz1esuH7BOZAGEZfLRCHJ0GVCSssg== Message-ID: Date: Tue, 24 Mar 2020 15:55:33 +1100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.5.0 MIME-Version: 1.0 In-Reply-To: Content-Language: en-US Cc: Greg Kroah-Hartman , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, "Aneesh Kumar K.V" , Robin Murphy X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" On 24/03/2020 14:37, Alexey Kardashevskiy wrote: > > > On 24/03/2020 04:20, Christoph Hellwig wrote: >> On Mon, Mar 23, 2020 at 07:58:01PM +1100, Alexey Kardashevskiy wrote: >>>>> 0x100.0000.0000 .. 0x101.0000.0000 >>>>> >>>>> 2x4G, each is 1TB aligned. And we can map directly only the first 4GB >>>>> (because of the maximum IOMMU table size) but not the other. And 1:1 on >>>>> that "pseries" is done with offset=0x0800.0000.0000.0000. >>>>> >>>>> So we want to check every bus address against dev->bus_dma_limit, not >>>>> dev->coherent_dma_mask. In the example above I'd set bus_dma_limit to >>>>> 0x0800.0001.0000.0000 and 1:1 mapping for the second 4GB would not be >>>>> tried. Does this sound reasonable? Thanks, >>>> >>>> bus_dma_limit is just another limiting factor applied on top of >>>> coherent_dma_mask or dma_mask respectively. >>> >>> This is not enough for the task: in my example, I'd set bus limit to >>> 0x0800.0001.0000.0000 but this would disable bypass for all RAM >>> addresses - the first and the second 4GB blocks. >> >> So what about something like the version here: >> >> http://git.infradead.org/users/hch/misc.git/shortlog/refs/heads/dma-bypass.3 > > > dma_alloc_direct() and dma_map_direct() do the same thing now which is > good, did I miss anything else? > > This lets us disable bypass automatically if this weird memory appears > in the system but does not let us have 1:1 after that even for normal > RAM. Thanks, Ah no, does not help much, simple setting dma_ops_bypass will though. But eventually, in this function: static inline bool dma_map_direct(struct device *dev, const struct dma_map_ops *ops) { if (likely(!ops)) return true; if (!dev->dma_ops_bypass) return false; return min_not_zero(*dev->dma_mask, dev->bus_dma_limit) >= dma_direct_get_required_mask(dev); } we rather want it to take a dma handle and a size, and add if (dev->bus_dma_limit) return dev->bus_dma_limit > dma_handle + size; where dma_handle=phys_to_dma(dev, phys) (I am not doing it here as unmap needs the same test and it does not receive phys as a parameter). -- Alexey _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu