From patchwork Thu Oct 17 10:48:35 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Wang X-Patchwork-Id: 11195437 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 9C55114E5 for ; Thu, 17 Oct 2019 10:51:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 70DB721D7A for ; Thu, 17 Oct 2019 10:51:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2409122AbfJQKvt (ORCPT ); Thu, 17 Oct 2019 06:51:49 -0400 Received: from mx1.redhat.com ([209.132.183.28]:39866 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2409109AbfJQKvt (ORCPT ); Thu, 17 Oct 2019 06:51:49 -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 5DEBC3082DDD; Thu, 17 Oct 2019 10:51:48 +0000 (UTC) Received: from jason-ThinkPad-X1-Carbon-6th.redhat.com (ovpn-12-185.pek2.redhat.com [10.72.12.185]) by smtp.corp.redhat.com (Postfix) with ESMTP id B33845D70D; Thu, 17 Oct 2019 10:51:23 +0000 (UTC) From: Jason Wang To: kvm@vger.kernel.org, linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, intel-gvt-dev@lists.freedesktop.org, kwankhede@nvidia.com, alex.williamson@redhat.com, mst@redhat.com, tiwei.bie@intel.com Cc: virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, cohuck@redhat.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, zhenyuw@linux.intel.com, zhi.a.wang@intel.com, jani.nikula@linux.intel.com, joonas.lahtinen@linux.intel.com, rodrigo.vivi@intel.com, airlied@linux.ie, daniel@ffwll.ch, farman@linux.ibm.com, pasic@linux.ibm.com, sebott@linux.ibm.com, oberpar@linux.ibm.com, heiko.carstens@de.ibm.com, gor@linux.ibm.com, borntraeger@de.ibm.com, akrowiak@linux.ibm.com, freude@linux.ibm.com, lingshan.zhu@intel.com, idos@mellanox.com, eperezma@redhat.com, lulu@redhat.com, parav@mellanox.com, christophe.de.dinechin@gmail.com, kevin.tian@intel.com, stefanha@redhat.com, Jason Wang Subject: [PATCH V4 5/6] virtio: introduce a mdev based transport Date: Thu, 17 Oct 2019 18:48:35 +0800 Message-Id: <20191017104836.32464-6-jasowang@redhat.com> In-Reply-To: <20191017104836.32464-1-jasowang@redhat.com> References: <20191017104836.32464-1-jasowang@redhat.com> MIME-Version: 1.0 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 [10.5.110.46]); Thu, 17 Oct 2019 10:51:48 +0000 (UTC) Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org This patch introduces a new mdev 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-mdev driver will be registered to the mdev bus, when a new virtio-mdev device is probed, it will register the device with mdev based config ops. This means it is a software transport between mdev driver and mdev device. The transport was implemented through device specific ops which is a part of mdev_parent_ops now. Signed-off-by: Jason Wang --- drivers/virtio/Kconfig | 7 + drivers/virtio/Makefile | 1 + drivers/virtio/virtio_mdev.c | 409 +++++++++++++++++++++++++++++++++++ 3 files changed, 417 insertions(+) create mode 100644 drivers/virtio/virtio_mdev.c diff --git a/drivers/virtio/Kconfig b/drivers/virtio/Kconfig index 078615cf2afc..8d18722ab572 100644 --- a/drivers/virtio/Kconfig +++ b/drivers/virtio/Kconfig @@ -43,6 +43,13 @@ config VIRTIO_PCI_LEGACY If unsure, say Y. +config VIRTIO_MDEV_DEVICE + tristate "VIRTIO driver for Mediated devices" + depends on VFIO_MDEV && VIRTIO + default n + help + VIRTIO based driver for Mediated devices. + config VIRTIO_PMEM tristate "Support for virtio pmem driver" depends on VIRTIO diff --git a/drivers/virtio/Makefile b/drivers/virtio/Makefile index 3a2b5c5dcf46..ebc7fa15ae82 100644 --- a/drivers/virtio/Makefile +++ b/drivers/virtio/Makefile @@ -6,3 +6,4 @@ 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_MDEV_DEVICE) += virtio_mdev.o diff --git a/drivers/virtio/virtio_mdev.c b/drivers/virtio/virtio_mdev.c new file mode 100644 index 000000000000..24c0df5ffe77 --- /dev/null +++ b/drivers/virtio/virtio_mdev.c @@ -0,0 +1,409 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * VIRTIO based driver for Mediated device + * + * Copyright (c) 2019, Red Hat. All rights reserved. + * Author: Jason Wang + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define DRIVER_VERSION "0.1" +#define DRIVER_AUTHOR "Red Hat Corporation" +#define DRIVER_DESC "VIRTIO based driver for Mediated device" + +#define to_virtio_mdev_device(dev) \ + container_of(dev, struct virtio_mdev_device, vdev) + +struct virtio_mdev_device { + struct virtio_device vdev; + struct mdev_device *mdev; + unsigned long version; + + /* The lock to protect virtqueue list */ + spinlock_t lock; + /* List of virtio_mdev_vq_info */ + struct list_head virtqueues; +}; + +struct virtio_mdev_vq_info { + /* the actual virtqueue */ + struct virtqueue *vq; + + /* the list node for the virtqueues list */ + struct list_head node; +}; + +static struct mdev_device *vm_get_mdev(struct virtio_device *vdev) +{ + struct virtio_mdev_device *vm_dev = to_virtio_mdev_device(vdev); + struct mdev_device *mdev = vm_dev->mdev; + + return mdev; +} + +static void virtio_mdev_get(struct virtio_device *vdev, unsigned offset, + void *buf, unsigned len) +{ + struct mdev_device *mdev = vm_get_mdev(vdev); + const struct virtio_mdev_device_ops *ops = mdev_get_dev_ops(mdev); + + ops->get_config(mdev, offset, buf, len); +} + +static void virtio_mdev_set(struct virtio_device *vdev, unsigned offset, + const void *buf, unsigned len) +{ + struct mdev_device *mdev = vm_get_mdev(vdev); + const struct virtio_mdev_device_ops *ops = mdev_get_dev_ops(mdev); + + ops->set_config(mdev, offset, buf, len); +} + +static u32 virtio_mdev_generation(struct virtio_device *vdev) +{ + struct mdev_device *mdev = vm_get_mdev(vdev); + const struct virtio_mdev_device_ops *ops = mdev_get_dev_ops(mdev); + + return ops->get_generation(mdev); +} + +static u8 virtio_mdev_get_status(struct virtio_device *vdev) +{ + struct mdev_device *mdev = vm_get_mdev(vdev); + const struct virtio_mdev_device_ops *ops = mdev_get_dev_ops(mdev); + + return ops->get_status(mdev); +} + +static void virtio_mdev_set_status(struct virtio_device *vdev, u8 status) +{ + struct mdev_device *mdev = vm_get_mdev(vdev); + const struct virtio_mdev_device_ops *ops = mdev_get_dev_ops(mdev); + + return ops->set_status(mdev, status); +} + +static void virtio_mdev_reset(struct virtio_device *vdev) +{ + struct mdev_device *mdev = vm_get_mdev(vdev); + const struct virtio_mdev_device_ops *ops = mdev_get_dev_ops(mdev); + + return ops->set_status(mdev, 0); +} + +static bool virtio_mdev_notify(struct virtqueue *vq) +{ + struct mdev_device *mdev = vm_get_mdev(vq->vdev); + const struct virtio_mdev_device_ops *ops = mdev_get_dev_ops(mdev); + + ops->kick_vq(mdev, vq->index); + + return true; +} + +static irqreturn_t virtio_mdev_config_cb(void *private) +{ + struct virtio_mdev_device *vm_dev = private; + + virtio_config_changed(&vm_dev->vdev); + + return IRQ_HANDLED; +} + +static irqreturn_t virtio_mdev_virtqueue_cb(void *private) +{ + struct virtio_mdev_vq_info *info = private; + + return vring_interrupt(0, info->vq); +} + +static struct virtqueue * +virtio_mdev_setup_vq(struct virtio_device *vdev, unsigned index, + void (*callback)(struct virtqueue *vq), + const char *name, bool ctx) +{ + struct virtio_mdev_device *vm_dev = to_virtio_mdev_device(vdev); + struct mdev_device *mdev = vm_get_mdev(vdev); + const struct virtio_mdev_device_ops *ops = mdev_get_dev_ops(mdev); + struct virtio_mdev_vq_info *info; + struct virtio_mdev_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(mdev, 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(mdev); + if (num == 0) { + err = -ENOENT; + goto error_new_virtqueue; + } + + /* Create the vring */ + align = ops->get_vq_align(mdev); + vq = vring_create_virtqueue(index, num, align, vdev, + true, true, ctx, + virtio_mdev_notify, callback, name); + if (!vq) { + err = -ENOMEM; + goto error_new_virtqueue; + } + + /* Setup virtqueue callback */ + cb.callback = virtio_mdev_virtqueue_cb; + cb.private = info; + ops->set_vq_cb(mdev, index, &cb); + ops->set_vq_num(mdev, 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(mdev, index, + desc_addr, driver_addr, + device_addr)) { + err = -EINVAL; + goto err_vq; + } + + ops->set_vq_ready(mdev, index, 1); + + vq->priv = info; + info->vq = vq; + + spin_lock_irqsave(&vm_dev->lock, flags); + list_add(&info->node, &vm_dev->virtqueues); + spin_unlock_irqrestore(&vm_dev->lock, flags); + + return vq; + +err_vq: + vring_del_virtqueue(vq); +error_new_virtqueue: + ops->set_vq_ready(mdev, index, 0); + WARN_ON(ops->get_vq_ready(mdev, index)); + kfree(info); + return ERR_PTR(err); + +} + +static void virtio_mdev_del_vq(struct virtqueue *vq) +{ + struct virtio_mdev_device *vm_dev = to_virtio_mdev_device(vq->vdev); + struct mdev_device *mdev = vm_dev->mdev; + const struct virtio_mdev_device_ops *ops = mdev_get_dev_ops(mdev); + struct virtio_mdev_vq_info *info = vq->priv; + unsigned int index = vq->index; + unsigned long flags; + + spin_lock_irqsave(&vm_dev->lock, flags); + list_del(&info->node); + spin_unlock_irqrestore(&vm_dev->lock, flags); + + /* Select and deactivate the queue */ + ops->set_vq_ready(mdev, index, 0); + WARN_ON(ops->get_vq_ready(mdev, index)); + + vring_del_virtqueue(vq); + + kfree(info); +} + +static void virtio_mdev_del_vqs(struct virtio_device *vdev) +{ + struct virtqueue *vq, *n; + + list_for_each_entry_safe(vq, n, &vdev->vqs, list) + virtio_mdev_del_vq(vq); +} + +static int virtio_mdev_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_mdev_device *vm_dev = to_virtio_mdev_device(vdev); + struct mdev_device *mdev = vm_get_mdev(vdev); + const struct virtio_mdev_device_ops *ops = mdev_get_dev_ops(mdev); + struct virtio_mdev_callback cb; + int i, err, queue_idx = 0; + + for (i = 0; i < nvqs; ++i) { + if (!names[i]) { + vqs[i] = NULL; + continue; + } + + vqs[i] = virtio_mdev_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_mdev_config_cb; + cb.private = vm_dev; + ops->set_config_cb(mdev, &cb); + + return 0; + +err_setup_vq: + virtio_mdev_del_vqs(vdev); + return err; +} + +static u64 virtio_mdev_get_features(struct virtio_device *vdev) +{ + struct mdev_device *mdev = vm_get_mdev(vdev); + const struct virtio_mdev_device_ops *ops = mdev_get_dev_ops(mdev); + + return ops->get_features(mdev); +} + +static int virtio_mdev_finalize_features(struct virtio_device *vdev) +{ + struct mdev_device *mdev = vm_get_mdev(vdev); + const struct virtio_mdev_device_ops *ops = mdev_get_dev_ops(mdev); + + /* Give virtio_ring a chance to accept features. */ + vring_transport_features(vdev); + + return ops->set_features(mdev, vdev->features); +} + +static const char *virtio_mdev_bus_name(struct virtio_device *vdev) +{ + struct virtio_mdev_device *vm_dev = to_virtio_mdev_device(vdev); + struct mdev_device *mdev = vm_dev->mdev; + + return dev_name(mdev_dev(mdev)); +} + +static const struct virtio_config_ops virtio_mdev_config_ops = { + .get = virtio_mdev_get, + .set = virtio_mdev_set, + .generation = virtio_mdev_generation, + .get_status = virtio_mdev_get_status, + .set_status = virtio_mdev_set_status, + .reset = virtio_mdev_reset, + .find_vqs = virtio_mdev_find_vqs, + .del_vqs = virtio_mdev_del_vqs, + .get_features = virtio_mdev_get_features, + .finalize_features = virtio_mdev_finalize_features, + .bus_name = virtio_mdev_bus_name, +}; + +static void virtio_mdev_release_dev(struct device *_d) +{ + struct virtio_device *vdev = + container_of(_d, struct virtio_device, dev); + struct virtio_mdev_device *vm_dev = + container_of(vdev, struct virtio_mdev_device, vdev); + + devm_kfree(_d, vm_dev); +} + +static int virtio_mdev_probe(struct device *dev) +{ + struct mdev_device *mdev = mdev_from_dev(dev); + const struct virtio_mdev_device_ops *ops = mdev_get_dev_ops(mdev); + struct virtio_mdev_device *vm_dev; + int rc; + + vm_dev = devm_kzalloc(dev, sizeof(*vm_dev), GFP_KERNEL); + if (!vm_dev) + return -ENOMEM; + + vm_dev->vdev.dev.parent = dev; + vm_dev->vdev.dev.release = virtio_mdev_release_dev; + vm_dev->vdev.config = &virtio_mdev_config_ops; + vm_dev->mdev = mdev; + INIT_LIST_HEAD(&vm_dev->virtqueues); + spin_lock_init(&vm_dev->lock); + + vm_dev->version = ops->get_mdev_features(mdev); + if (vm_dev->version != VIRTIO_MDEV_F_VERSION_1) { + dev_err(dev, "VIRTIO_MDEV_F_VERSION_1 is mandatory\n"); + return -ENXIO; + } + + vm_dev->vdev.id.device = ops->get_device_id(mdev); + if (vm_dev->vdev.id.device == 0) + return -ENODEV; + + vm_dev->vdev.id.vendor = ops->get_vendor_id(mdev); + rc = register_virtio_device(&vm_dev->vdev); + if (rc) + put_device(dev); + else + dev_set_drvdata(dev, vm_dev); + + return rc; +} + +static void virtio_mdev_remove(struct device *dev) +{ + struct virtio_mdev_device *vm_dev = dev_get_drvdata(dev); + + unregister_virtio_device(&vm_dev->vdev); +} + +static const struct mdev_class_id id_table[] = { + { MDEV_CLASS_ID_VIRTIO }, + { 0 }, +}; + +MODULE_DEVICE_TABLE(mdev, id_table); + +static struct mdev_driver virtio_mdev_driver = { + .name = "virtio_mdev", + .probe = virtio_mdev_probe, + .remove = virtio_mdev_remove, + .id_table = id_table, +}; + +static int __init virtio_mdev_init(void) +{ + return mdev_register_driver(&virtio_mdev_driver, THIS_MODULE); +} + +static void __exit virtio_mdev_exit(void) +{ + mdev_unregister_driver(&virtio_mdev_driver); +} + +module_init(virtio_mdev_init) +module_exit(virtio_mdev_exit) + +MODULE_VERSION(DRIVER_VERSION); +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR(DRIVER_AUTHOR); +MODULE_DESCRIPTION(DRIVER_DESC);