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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_PASS 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 A07DEC04E53 for ; Wed, 15 May 2019 20:46:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6D34A20843 for ; Wed, 15 May 2019 20:46:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727137AbfEOUqT (ORCPT ); Wed, 15 May 2019 16:46:19 -0400 Received: from mx1.redhat.com ([209.132.183.28]:37562 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726170AbfEOUqS (ORCPT ); Wed, 15 May 2019 16:46:18 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 42E323082B46; Wed, 15 May 2019 20:46:17 +0000 (UTC) Received: from [10.36.116.133] (ovpn-116-133.ams2.redhat.com [10.36.116.133]) by smtp.corp.redhat.com (Postfix) with ESMTP id 4C6766266C; Wed, 15 May 2019 20:46:01 +0000 (UTC) Subject: Re: [PATCH v9 2/7] virtio-pmem: Add virtio pmem driver To: Pankaj Gupta , linux-nvdimm@lists.01.org, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, kvm@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-acpi@vger.kernel.org, qemu-devel@nongnu.org, linux-ext4@vger.kernel.org, linux-xfs@vger.kernel.org, mst@redhat.com Cc: dan.j.williams@intel.com, zwisler@kernel.org, vishal.l.verma@intel.com, dave.jiang@intel.com, jasowang@redhat.com, willy@infradead.org, rjw@rjwysocki.net, hch@infradead.org, lenb@kernel.org, jack@suse.cz, tytso@mit.edu, adilger.kernel@dilger.ca, darrick.wong@oracle.com, lcapitulino@redhat.com, kwolf@redhat.com, imammedo@redhat.com, jmoyer@redhat.com, nilal@redhat.com, riel@surriel.com, stefanha@redhat.com, aarcange@redhat.com, david@fromorbit.com, cohuck@redhat.com, xiaoguangrong.eric@gmail.com, pbonzini@redhat.com, kilobyte@angband.pl, yuval.shaia@oracle.com, jstaron@google.com References: <20190514145422.16923-1-pagupta@redhat.com> <20190514145422.16923-3-pagupta@redhat.com> From: David Hildenbrand Openpgp: preference=signencrypt Autocrypt: addr=david@redhat.com; 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Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <20190514145422.16923-3-pagupta@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.45]); Wed, 15 May 2019 20:46:17 +0000 (UTC) Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org > + vpmem->vdev = vdev; > + vdev->priv = vpmem; > + err = init_vq(vpmem); > + if (err) { > + dev_err(&vdev->dev, "failed to initialize virtio pmem vq's\n"); > + goto out_err; > + } > + > + virtio_cread(vpmem->vdev, struct virtio_pmem_config, > + start, &vpmem->start); > + virtio_cread(vpmem->vdev, struct virtio_pmem_config, > + size, &vpmem->size); > + > + res.start = vpmem->start; > + res.end = vpmem->start + vpmem->size-1; nit: " - 1;" > + vpmem->nd_desc.provider_name = "virtio-pmem"; > + vpmem->nd_desc.module = THIS_MODULE; > + > + vpmem->nvdimm_bus = nvdimm_bus_register(&vdev->dev, > + &vpmem->nd_desc); > + if (!vpmem->nvdimm_bus) { > + dev_err(&vdev->dev, "failed to register device with nvdimm_bus\n"); > + err = -ENXIO; > + goto out_vq; > + } > + > + dev_set_drvdata(&vdev->dev, vpmem->nvdimm_bus); > + > + ndr_desc.res = &res; > + ndr_desc.numa_node = nid; > + ndr_desc.flush = async_pmem_flush; > + set_bit(ND_REGION_PAGEMAP, &ndr_desc.flags); > + set_bit(ND_REGION_ASYNC, &ndr_desc.flags); > + nd_region = nvdimm_pmem_region_create(vpmem->nvdimm_bus, &ndr_desc); > + if (!nd_region) { > + dev_err(&vdev->dev, "failed to create nvdimm region\n"); > + err = -ENXIO; > + goto out_nd; > + } > + nd_region->provider_data = dev_to_virtio(nd_region->dev.parent->parent); > + return 0; > +out_nd: > + nvdimm_bus_unregister(vpmem->nvdimm_bus); > +out_vq: > + vdev->config->del_vqs(vdev); > +out_err: > + return err; > +} > + > +static void virtio_pmem_remove(struct virtio_device *vdev) > +{ > + struct nvdimm_bus *nvdimm_bus = dev_get_drvdata(&vdev->dev); > + > + nvdimm_bus_unregister(nvdimm_bus); > + vdev->config->del_vqs(vdev); > + vdev->config->reset(vdev); > +} > + > +static struct virtio_driver virtio_pmem_driver = { > + .driver.name = KBUILD_MODNAME, > + .driver.owner = THIS_MODULE, > + .id_table = id_table, > + .probe = virtio_pmem_probe, > + .remove = virtio_pmem_remove, > +}; > + > +module_virtio_driver(virtio_pmem_driver); > +MODULE_DEVICE_TABLE(virtio, id_table); > +MODULE_DESCRIPTION("Virtio pmem driver"); > +MODULE_LICENSE("GPL"); > diff --git a/drivers/nvdimm/virtio_pmem.h b/drivers/nvdimm/virtio_pmem.h > new file mode 100644 > index 000000000000..ab1da877575d > --- /dev/null > +++ b/drivers/nvdimm/virtio_pmem.h > @@ -0,0 +1,60 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > +/* > + * virtio_pmem.h: virtio pmem Driver > + * > + * Discovers persistent memory range information > + * from host and provides a virtio based flushing > + * interface. > + **/ > + > +#ifndef _LINUX_VIRTIO_PMEM_H > +#define _LINUX_VIRTIO_PMEM_H > + > +#include > +#include > +#include > +#include > +#include > +#include > + > +struct virtio_pmem_request { > + /* Host return status corresponding to flush request */ > + int ret; > + > + /* command name*/ > + char name[16]; So ... why are we sending string commands and expect native-endianess integers and don't define a proper request/response structure + request types in include/uapi/linux/virtio_pmem.h like struct virtio_pmem_resp { __virtio32 ret; } #define VIRTIO_PMEM_REQ_TYPE_FLUSH 1 struct virtio_pmem_req { __virtio16 type; } ... and this way we also define a proper endianess format for exchange and keep it extensible @MST, what's your take on this? -- Thanks, David / dhildenb