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=-5.5 required=3.0 tests=DKIM_ADSP_CUSTOM_MED, DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 54457C4CECE for ; Wed, 11 Mar 2020 19:32:34 +0000 (UTC) Received: from ml01.01.org (ml01.01.org [198.145.21.10]) (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 44FA52073E for ; Wed, 11 Mar 2020 19:32:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Ytxtuf3Q" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 44FA52073E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-nvdimm-bounces@lists.01.org Received: from ml01.vlan13.01.org (localhost [IPv6:::1]) by ml01.01.org (Postfix) with ESMTP id 4579910FC3764; Wed, 11 Mar 2020 12:33:24 -0700 (PDT) Received-SPF: Pass (mailfrom) identity=mailfrom; client-ip=2607:f8b0:4864:20::144; helo=mail-il1-x144.google.com; envelope-from=amir73il@gmail.com; receiver= Received: from mail-il1-x144.google.com (mail-il1-x144.google.com [IPv6:2607:f8b0:4864:20::144]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 4B73710FC3762 for ; Wed, 11 Mar 2020 12:33:21 -0700 (PDT) Received: by mail-il1-x144.google.com with SMTP id p1so3148698ils.12 for ; Wed, 11 Mar 2020 12:32:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=2mXGK5i6t3MsASMxT0lG83kEdxLaxyp7/VkTyiOzfWA=; b=Ytxtuf3QQxZWXFhnUaNGSp6HRtTjU2rvi2VTtDUKIWrIxcTF08sJcrGYYDSZ0cjYVi NC7Jr18qi45Tn2TxgwNtbFQJyxoGPpldN77YOO65Z1kc2htI75AljVGHwZtqXl4WFh09 II9VBsbHtPSWuTzSj8DU2x+vAkcTNO12e6wd0JHiEtKO2fSJv+IyvIKGAf31Vwlh/6le fGg/uJ53yaXQU8x+y+MF9ACDtFn+SNGFV7s3uD000Qka0NXvCcWm88thMuialB2aMbeW LTTNeVSpoAVa+tcRkDxn2Zcdp7Mw05sgFo6hkmJTrwxWy7LCnul4OZtHXyEwSBI41s5K c7lw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=2mXGK5i6t3MsASMxT0lG83kEdxLaxyp7/VkTyiOzfWA=; b=tM1hHUpN2+kRnGoRpNfdRTzjfc8VqM3crQpL4leVzvDEsnWTx3settsOmJXryuLJrv OCQO7sG3F8LGpcDAkxtG+yxppKcXWM3F6Q8x1jtKHKv/dbqAW039JryvwOzFr6unsv8W VeRR1VgCAPjSz71LLEjtxLNjqjBELi0fSGs50XjExkxyyR22LUZv9lm5JkeAGuGBKOIJ 6M4VEzWlzeDe6vK745oHmiIT+9mFbFdsgarrJyBcZ+c4OmQ3dvn+FK06p07nMVqyLeZq UkhBC4428sXJoAjr5bsHohYBzK+J2Mgn2C04o/zqkPkHB/+JCTNkznQtgZW5Y9TP+qP8 VNdQ== X-Gm-Message-State: ANhLgQ1YipW6Db8IuPul5udASj8PMVnRJUTHFybV4WS81WaZP9fs8S1j RswgTEyEWpUYMa3qR7zKrQ7OnsrXyx0O9tWHKZM= X-Google-Smtp-Source: ADFU+vv0awZxCRaxLNBtprB5PP6XxG/N9GF146xOmYHuD2pw5NVQaGTRY7PIOTDoXzSifgO7fcQC19biON6GFFI5zP8= X-Received: by 2002:a92:6f10:: with SMTP id k16mr4651309ilc.275.1583955149310; Wed, 11 Mar 2020 12:32:29 -0700 (PDT) MIME-Version: 1.0 References: <20200304165845.3081-1-vgoyal@redhat.com> <20200311184830.GC83257@redhat.com> In-Reply-To: <20200311184830.GC83257@redhat.com> From: Amir Goldstein Date: Wed, 11 Mar 2020 21:32:17 +0200 Message-ID: Subject: Re: [PATCH 00/20] virtiofs: Add DAX support To: Vivek Goyal Message-ID-Hash: DPJI5HDTVROTDIDOYWDJSIVU2OGH4RVS X-Message-ID-Hash: DPJI5HDTVROTDIDOYWDJSIVU2OGH4RVS X-MailFrom: amir73il@gmail.com X-Mailman-Rule-Hits: nonmember-moderation X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation CC: linux-fsdevel , linux-kernel , linux-nvdimm , virtio-fs@redhat.com, Miklos Szeredi , Stefan Hajnoczi , "Dr. David Alan Gilbert" , mst@redhat.com X-Mailman-Version: 3.1.1 Precedence: list List-Id: "Linux-nvdimm developer list." Archived-At: List-Archive: List-Help: List-Post: List-Subscribe: List-Unsubscribe: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit On Wed, Mar 11, 2020 at 8:48 PM Vivek Goyal wrote: > > On Wed, Mar 11, 2020 at 07:22:51AM +0200, Amir Goldstein wrote: > > On Wed, Mar 4, 2020 at 7:01 PM Vivek Goyal wrote: > > > > > > Hi, > > > > > > This patch series adds DAX support to virtiofs filesystem. This allows > > > bypassing guest page cache and allows mapping host page cache directly > > > in guest address space. > > > > > > When a page of file is needed, guest sends a request to map that page > > > (in host page cache) in qemu address space. Inside guest this is > > > a physical memory range controlled by virtiofs device. And guest > > > directly maps this physical address range using DAX and hence gets > > > access to file data on host. > > > > > > This can speed up things considerably in many situations. Also this > > > can result in substantial memory savings as file data does not have > > > to be copied in guest and it is directly accessed from host page > > > cache. > > > > > > Most of the changes are limited to fuse/virtiofs. There are couple > > > of changes needed in generic dax infrastructure and couple of changes > > > in virtio to be able to access shared memory region. > > > > > > These patches apply on top of 5.6-rc4 and are also available here. > > > > > > https://github.com/rhvgoyal/linux/commits/vivek-04-march-2020 > > > > > > Any review or feedback is welcome. > > > > > [...] > > > drivers/dax/super.c | 3 +- > > > drivers/virtio/virtio_mmio.c | 32 + > > > drivers/virtio/virtio_pci_modern.c | 107 +++ > > > fs/dax.c | 66 +- > > > fs/fuse/dir.c | 2 + > > > fs/fuse/file.c | 1162 +++++++++++++++++++++++++++- > > > > That's a big addition to already big file.c. > > Maybe split dax specific code to dax.c? > > Can be a post series cleanup too. > > How about fs/fuse/iomap.c instead. This will have all the iomap related logic > as well as all the dax range allocation/free logic which is required > by iomap logic. That moves about 900 lines of code from file.c to iomap.c > Fine by me. I didn't take time to study the code in file.c I just noticed is has grown a lot bigger and wasn't sure that it made sense. Up to you. Only if you think the result would be nicer to maintain. Thanks, Amir. _______________________________________________ Linux-nvdimm mailing list -- linux-nvdimm@lists.01.org To unsubscribe send an email to linux-nvdimm-leave@lists.01.org