From patchwork Mon Feb 10 03:56:07 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Wang X-Patchwork-Id: 11372441 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id DB3B514B4 for ; Mon, 10 Feb 2020 04:01:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A5EEA20870 for ; Mon, 10 Feb 2020 04:01:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="QtT63y/g" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727481AbgBJEBy (ORCPT ); Sun, 9 Feb 2020 23:01:54 -0500 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:28725 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727600AbgBJEBx (ORCPT ); Sun, 9 Feb 2020 23:01:53 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1581307311; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=v/WUSss28k1zXPtrvX7+juH17o1JUa0tz8B/5GaiG18=; b=QtT63y/gIOKgITrYygUqD/ZKplxo9+a15Eprl7UO+VZK2chfY7VR1PaYQoljBSKbujJCOC ABnY2XcnFhdl/JF+8fvo+zxmd8xzLFJeRUmNHU/oHJ+4kBSPmy9iIoSiOfW5vm7CZIdimo xzsNU/BI5zjyiLpUxHoLKpGyD1eE0ow= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-10-3xRfERGJM96D1DsmyiE9tQ-1; Sun, 09 Feb 2020 23:01:49 -0500 X-MC-Unique: 3xRfERGJM96D1DsmyiE9tQ-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id EC2BF8017CC; Mon, 10 Feb 2020 04:01:46 +0000 (UTC) Received: from jason-ThinkPad-X1-Carbon-6th.redhat.com (ovpn-13-219.pek2.redhat.com [10.72.13.219]) by smtp.corp.redhat.com (Postfix) with ESMTP id 3F958101D481; Mon, 10 Feb 2020 04:00:40 +0000 (UTC) From: Jason Wang To: mst@redhat.com, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org Cc: tiwei.bie@intel.com, jgg@mellanox.com, maxime.coquelin@redhat.com, cunming.liang@intel.com, zhihong.wang@intel.com, rob.miller@broadcom.com, xiao.w.wang@intel.com, haotian.wang@sifive.com, lingshan.zhu@intel.com, eperezma@redhat.com, lulu@redhat.com, parav@mellanox.com, kevin.tian@intel.com, stefanha@redhat.com, rdunlap@infradead.org, hch@infradead.org, aadam@redhat.com, jiri@mellanox.com, shahafs@mellanox.com, hanand@xilinx.com, mhabets@solarflare.com, Jason Wang Subject: [PATCH V2 4/5] virtio: introduce a vDPA based transport Date: Mon, 10 Feb 2020 11:56:07 +0800 Message-Id: <20200210035608.10002-5-jasowang@redhat.com> In-Reply-To: <20200210035608.10002-1-jasowang@redhat.com> References: <20200210035608.10002-1-jasowang@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org This patch introduces a vDPA transport for virtio. This is used to use kernel virtio driver to drive the mediated device that is capable of populating virtqueue directly. A new virtio-vdpa driver will be registered to the vDPA bus, when a new virtio-vdpa device is probed, it will register the device with vdpa based config ops. This means it is a software transport between vDPA driver and vDPA device. The transport was implemented through bus_ops of vDPA parent. Signed-off-by: Jason Wang --- drivers/virtio/Kconfig | 13 ++ drivers/virtio/Makefile | 1 + drivers/virtio/virtio_vdpa.c | 392 +++++++++++++++++++++++++++++++++++ 3 files changed, 406 insertions(+) create mode 100644 drivers/virtio/virtio_vdpa.c diff --git a/drivers/virtio/Kconfig b/drivers/virtio/Kconfig index 9c4fdb64d9ac..0df3676b0f4f 100644 --- a/drivers/virtio/Kconfig +++ b/drivers/virtio/Kconfig @@ -43,6 +43,19 @@ config VIRTIO_PCI_LEGACY If unsure, say Y. +config VIRTIO_VDPA + tristate "vDPA driver for virtio devices" + select VDPA + select VIRTIO + help + This driver provides support for virtio based paravirtual + device driver over vDPA bus. For this to be useful, you need + an appropriate vDPA device implementation that operates on a + physical device to allow the datapath of virtio to be + offloaded to hardware. + + If unsure, say M. + config VIRTIO_PMEM tristate "Support for virtio pmem driver" depends on VIRTIO diff --git a/drivers/virtio/Makefile b/drivers/virtio/Makefile index fdf5eacd0d0a..3407ac03fe60 100644 --- a/drivers/virtio/Makefile +++ b/drivers/virtio/Makefile @@ -6,4 +6,5 @@ virtio_pci-y := virtio_pci_modern.o virtio_pci_common.o virtio_pci-$(CONFIG_VIRTIO_PCI_LEGACY) += virtio_pci_legacy.o obj-$(CONFIG_VIRTIO_BALLOON) += virtio_balloon.o obj-$(CONFIG_VIRTIO_INPUT) += virtio_input.o +obj-$(CONFIG_VIRTIO_VDPA) += virtio_vdpa.o obj-$(CONFIG_VDPA) += vdpa/ diff --git a/drivers/virtio/virtio_vdpa.c b/drivers/virtio/virtio_vdpa.c new file mode 100644 index 000000000000..077796087abf --- /dev/null +++ b/drivers/virtio/virtio_vdpa.c @@ -0,0 +1,392 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * VIRTIO based driver for vDPA device + * + * Copyright (c) 2020, Red Hat. All rights reserved. + * Author: Jason Wang + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define MOD_VERSION "0.1" +#define MOD_AUTHOR "Jason Wang " +#define MOD_DESC "vDPA bus driver for virtio devices" +#define MOD_LICENSE "GPL v2" + +struct virtio_vdpa_device { + struct virtio_device vdev; + struct vdpa_device *vdpa; + u64 features; + + /* The lock to protect virtqueue list */ + spinlock_t lock; + /* List of virtio_vdpa_vq_info */ + struct list_head virtqueues; +}; + +struct virtio_vdpa_vq_info { + /* the actual virtqueue */ + struct virtqueue *vq; + + /* the list node for the virtqueues list */ + struct list_head node; +}; + +static inline struct virtio_vdpa_device * +to_virtio_vdpa_device(struct virtio_device *dev) +{ + return container_of(dev, struct virtio_vdpa_device, vdev); +} + +static struct vdpa_device *vd_get_vdpa(struct virtio_device *vdev) +{ + return to_virtio_vdpa_device(vdev)->vdpa; +} + +static void virtio_vdpa_get(struct virtio_device *vdev, unsigned offset, + void *buf, unsigned len) +{ + struct vdpa_device *vdpa = vd_get_vdpa(vdev); + const struct vdpa_config_ops *ops = vdpa->config; + + ops->get_config(vdpa, offset, buf, len); +} + +static void virtio_vdpa_set(struct virtio_device *vdev, unsigned offset, + const void *buf, unsigned len) +{ + struct vdpa_device *vdpa = vd_get_vdpa(vdev); + const struct vdpa_config_ops *ops = vdpa->config; + + ops->set_config(vdpa, offset, buf, len); +} + +static u32 virtio_vdpa_generation(struct virtio_device *vdev) +{ + struct vdpa_device *vdpa = vd_get_vdpa(vdev); + const struct vdpa_config_ops *ops = vdpa->config; + + if (ops->get_generation) + return ops->get_generation(vdpa); + + return 0; +} + +static u8 virtio_vdpa_get_status(struct virtio_device *vdev) +{ + struct vdpa_device *vdpa = vd_get_vdpa(vdev); + const struct vdpa_config_ops *ops = vdpa->config; + + return ops->get_status(vdpa); +} + +static void virtio_vdpa_set_status(struct virtio_device *vdev, u8 status) +{ + struct vdpa_device *vdpa = vd_get_vdpa(vdev); + const struct vdpa_config_ops *ops = vdpa->config; + + return ops->set_status(vdpa, status); +} + +static void virtio_vdpa_reset(struct virtio_device *vdev) +{ + struct vdpa_device *vdpa = vd_get_vdpa(vdev); + const struct vdpa_config_ops *ops = vdpa->config; + + return ops->set_status(vdpa, 0); +} + +static bool virtio_vdpa_notify(struct virtqueue *vq) +{ + struct vdpa_device *vdpa = vd_get_vdpa(vq->vdev); + const struct vdpa_config_ops *ops = vdpa->config; + + ops->kick_vq(vdpa, vq->index); + + return true; +} + +static irqreturn_t virtio_vdpa_config_cb(void *private) +{ + struct virtio_vdpa_device *vd_dev = private; + + virtio_config_changed(&vd_dev->vdev); + + return IRQ_HANDLED; +} + +static irqreturn_t virtio_vdpa_virtqueue_cb(void *private) +{ + struct virtio_vdpa_vq_info *info = private; + + return vring_interrupt(0, info->vq); +} + +static struct virtqueue * +virtio_vdpa_setup_vq(struct virtio_device *vdev, unsigned int index, + void (*callback)(struct virtqueue *vq), + const char *name, bool ctx) +{ + struct virtio_vdpa_device *vd_dev = to_virtio_vdpa_device(vdev); + struct vdpa_device *vdpa = vd_get_vdpa(vdev); + const struct vdpa_config_ops *ops = vdpa->config; + struct virtio_vdpa_vq_info *info; + struct vdpa_callback cb; + struct virtqueue *vq; + u64 desc_addr, driver_addr, device_addr; + unsigned long flags; + u32 align, num; + int err; + + if (!name) + return NULL; + + /* Queue shouldn't already be set up. */ + if (ops->get_vq_ready(vdpa, index)) + return ERR_PTR(-ENOENT); + + /* Allocate and fill out our active queue description */ + info = kmalloc(sizeof(*info), GFP_KERNEL); + if (!info) + return ERR_PTR(-ENOMEM); + + num = ops->get_vq_num_max(vdpa); + if (num == 0) { + err = -ENOENT; + goto error_new_virtqueue; + } + + /* Create the vring */ + align = ops->get_vq_align(vdpa); + vq = vring_create_virtqueue(index, num, align, vdev, + true, true, ctx, + virtio_vdpa_notify, callback, name); + if (!vq) { + err = -ENOMEM; + goto error_new_virtqueue; + } + + /* Setup virtqueue callback */ + cb.callback = virtio_vdpa_virtqueue_cb; + cb.private = info; + ops->set_vq_cb(vdpa, index, &cb); + ops->set_vq_num(vdpa, index, virtqueue_get_vring_size(vq)); + + desc_addr = virtqueue_get_desc_addr(vq); + driver_addr = virtqueue_get_avail_addr(vq); + device_addr = virtqueue_get_used_addr(vq); + + if (ops->set_vq_address(vdpa, index, + desc_addr, driver_addr, + device_addr)) { + err = -EINVAL; + goto err_vq; + } + + ops->set_vq_ready(vdpa, index, 1); + + vq->priv = info; + info->vq = vq; + + spin_lock_irqsave(&vd_dev->lock, flags); + list_add(&info->node, &vd_dev->virtqueues); + spin_unlock_irqrestore(&vd_dev->lock, flags); + + return vq; + +err_vq: + vring_del_virtqueue(vq); +error_new_virtqueue: + ops->set_vq_ready(vdpa, index, 0); + /* VDPA driver should make sure vq is stopeed here */ + WARN_ON(ops->get_vq_ready(vdpa, index)); + kfree(info); + return ERR_PTR(err); +} + +static void virtio_vdpa_del_vq(struct virtqueue *vq) +{ + struct virtio_vdpa_device *vd_dev = to_virtio_vdpa_device(vq->vdev); + struct vdpa_device *vdpa = vd_dev->vdpa; + const struct vdpa_config_ops *ops = vdpa->config; + struct virtio_vdpa_vq_info *info = vq->priv; + unsigned int index = vq->index; + unsigned long flags; + + spin_lock_irqsave(&vd_dev->lock, flags); + list_del(&info->node); + spin_unlock_irqrestore(&vd_dev->lock, flags); + + /* Select and deactivate the queue */ + ops->set_vq_ready(vdpa, index, 0); + WARN_ON(ops->get_vq_ready(vdpa, index)); + + vring_del_virtqueue(vq); + + kfree(info); +} + +static void virtio_vdpa_del_vqs(struct virtio_device *vdev) +{ + struct virtqueue *vq, *n; + + list_for_each_entry_safe(vq, n, &vdev->vqs, list) + virtio_vdpa_del_vq(vq); +} + +static int virtio_vdpa_find_vqs(struct virtio_device *vdev, unsigned nvqs, + struct virtqueue *vqs[], + vq_callback_t *callbacks[], + const char * const names[], + const bool *ctx, + struct irq_affinity *desc) +{ + struct virtio_vdpa_device *vd_dev = to_virtio_vdpa_device(vdev); + struct vdpa_device *vdpa = vd_get_vdpa(vdev); + const struct vdpa_config_ops *ops = vdpa->config; + struct vdpa_callback cb; + int i, err, queue_idx = 0; + + for (i = 0; i < nvqs; ++i) { + if (!names[i]) { + vqs[i] = NULL; + continue; + } + + vqs[i] = virtio_vdpa_setup_vq(vdev, queue_idx++, + callbacks[i], names[i], ctx ? + ctx[i] : false); + if (IS_ERR(vqs[i])) { + err = PTR_ERR(vqs[i]); + goto err_setup_vq; + } + } + + cb.callback = virtio_vdpa_config_cb; + cb.private = vd_dev; + ops->set_config_cb(vdpa, &cb); + + return 0; + +err_setup_vq: + virtio_vdpa_del_vqs(vdev); + return err; +} + +static u64 virtio_vdpa_get_features(struct virtio_device *vdev) +{ + struct vdpa_device *vdpa = vd_get_vdpa(vdev); + const struct vdpa_config_ops *ops = vdpa->config; + + return ops->get_features(vdpa); +} + +static int virtio_vdpa_finalize_features(struct virtio_device *vdev) +{ + struct vdpa_device *vdpa = vd_get_vdpa(vdev); + const struct vdpa_config_ops *ops = vdpa->config; + + /* Give virtio_ring a chance to accept features. */ + vring_transport_features(vdev); + + return ops->set_features(vdpa, vdev->features); +} + +static const char *virtio_vdpa_bus_name(struct virtio_device *vdev) +{ + struct virtio_vdpa_device *vd_dev = to_virtio_vdpa_device(vdev); + struct vdpa_device *vdpa = vd_dev->vdpa; + + return dev_name(&vdpa->dev); +} + +static const struct virtio_config_ops virtio_vdpa_config_ops = { + .get = virtio_vdpa_get, + .set = virtio_vdpa_set, + .generation = virtio_vdpa_generation, + .get_status = virtio_vdpa_get_status, + .set_status = virtio_vdpa_set_status, + .reset = virtio_vdpa_reset, + .find_vqs = virtio_vdpa_find_vqs, + .del_vqs = virtio_vdpa_del_vqs, + .get_features = virtio_vdpa_get_features, + .finalize_features = virtio_vdpa_finalize_features, + .bus_name = virtio_vdpa_bus_name, +}; + +static void virtio_vdpa_release_dev(struct device *_d) +{ + struct virtio_device *vdev = + container_of(_d, struct virtio_device, dev); + struct virtio_vdpa_device *vd_dev = + container_of(vdev, struct virtio_vdpa_device, vdev); + + kfree(vd_dev); +} + +static int virtio_vdpa_probe(struct vdpa_device *vdpa) +{ + const struct vdpa_config_ops *ops = vdpa->config; + struct virtio_vdpa_device *vd_dev; + int ret = -EINVAL; + + vd_dev = kzalloc(sizeof(*vd_dev), GFP_KERNEL); + if (!vd_dev) + return -ENOMEM; + + vd_dev->vdev.dev.parent = vdpa_get_dma_dev(vdpa); + vd_dev->vdev.dev.release = virtio_vdpa_release_dev; + vd_dev->vdev.config = &virtio_vdpa_config_ops; + vd_dev->vdpa = vdpa; + INIT_LIST_HEAD(&vd_dev->virtqueues); + spin_lock_init(&vd_dev->lock); + + vd_dev->vdev.id.device = ops->get_device_id(vdpa); + if (vd_dev->vdev.id.device == 0) + goto err; + + vd_dev->vdev.id.vendor = ops->get_vendor_id(vdpa); + ret = register_virtio_device(&vd_dev->vdev); + if (ret) + goto err; + + vdpa_set_drvdata(vdpa, vd_dev); + + return 0; + +err: + kfree(vd_dev); + return ret; +} + +static void virtio_vdpa_remove(struct vdpa_device *vdpa) +{ + struct virtio_vdpa_device *vd_dev = vdpa_get_drvdata(vdpa); + + unregister_virtio_device(&vd_dev->vdev); +} + +static struct vdpa_driver virtio_vdpa_driver = { + .driver = { + .name = "virtio_vdpa", + }, + .probe = virtio_vdpa_probe, + .remove = virtio_vdpa_remove, +}; + +module_vdpa_driver(virtio_vdpa_driver); + +MODULE_VERSION(MOD_VERSION); +MODULE_LICENSE(MOD_LICENSE); +MODULE_AUTHOR(MOD_AUTHOR); +MODULE_DESCRIPTION(MOD_DESC);