From patchwork Tue Sep 17 01:02:04 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tiwei Bie X-Patchwork-Id: 11147973 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 0AB0D1708 for ; Tue, 17 Sep 2019 01:06:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C103220678 for ; Tue, 17 Sep 2019 01:06:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388398AbfIQBGE (ORCPT ); Mon, 16 Sep 2019 21:06:04 -0400 Received: from mga04.intel.com ([192.55.52.120]:34819 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390965AbfIQBFH (ORCPT ); Mon, 16 Sep 2019 21:05:07 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga104.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 16 Sep 2019 18:05:06 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.64,514,1559545200"; d="scan'208";a="180612006" Received: from dpdk-virtio-tbie-2.sh.intel.com ([10.67.104.71]) by orsmga008.jf.intel.com with ESMTP; 16 Sep 2019 18:05:03 -0700 From: Tiwei Bie To: mst@redhat.com, jasowang@redhat.com, alex.williamson@redhat.com, maxime.coquelin@redhat.com Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, dan.daly@intel.com, cunming.liang@intel.com, zhihong.wang@intel.com, lingshan.zhu@intel.com, tiwei.bie@intel.com Subject: [RFC v4 3/3] vhost: introduce mdev based hardware backend Date: Tue, 17 Sep 2019 09:02:04 +0800 Message-Id: <20190917010204.30376-4-tiwei.bie@intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190917010204.30376-1-tiwei.bie@intel.com> References: <20190917010204.30376-1-tiwei.bie@intel.com> Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org More details about this patch can be found from the cover letter for now. Only compile test has been done for now. Signed-off-by: Tiwei Bie --- drivers/vhost/Kconfig | 9 + drivers/vhost/Makefile | 3 + drivers/vhost/mdev.c | 462 +++++++++++++++++++++++++++++++ drivers/vhost/vhost.c | 39 ++- drivers/vhost/vhost.h | 6 + include/uapi/linux/vhost.h | 10 + include/uapi/linux/vhost_types.h | 5 + 7 files changed, 528 insertions(+), 6 deletions(-) create mode 100644 drivers/vhost/mdev.c diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig index 3d03ccbd1adc..ef9783156d2e 100644 --- a/drivers/vhost/Kconfig +++ b/drivers/vhost/Kconfig @@ -34,6 +34,15 @@ config VHOST_VSOCK To compile this driver as a module, choose M here: the module will be called vhost_vsock. +config VHOST_MDEV + tristate "Mediated device based hardware vhost accelerator" + depends on EVENTFD && VFIO && VFIO_MDEV + select VHOST + default n + ---help--- + Say Y here to enable the vhost_mdev module + for use with hardware vhost accelerators + config VHOST tristate ---help--- diff --git a/drivers/vhost/Makefile b/drivers/vhost/Makefile index 6c6df24f770c..ad9c0f8c6d8c 100644 --- a/drivers/vhost/Makefile +++ b/drivers/vhost/Makefile @@ -10,4 +10,7 @@ vhost_vsock-y := vsock.o obj-$(CONFIG_VHOST_RING) += vringh.o +obj-$(CONFIG_VHOST_MDEV) += vhost_mdev.o +vhost_mdev-y := mdev.o + obj-$(CONFIG_VHOST) += vhost.o diff --git a/drivers/vhost/mdev.c b/drivers/vhost/mdev.c new file mode 100644 index 000000000000..8c6597aff45e --- /dev/null +++ b/drivers/vhost/mdev.c @@ -0,0 +1,462 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2018-2019 Intel Corporation. + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#include "vhost.h" + +struct vhost_mdev { + struct mutex mutex; + struct vhost_dev dev; + struct vhost_virtqueue *vqs; + int nvqs; + u64 state; + u64 features; + u64 acked_features; + struct vfio_group *vfio_group; + struct vfio_device *vfio_device; + struct mdev_device *mdev; +}; + +/* + * XXX + * We assume virtio_mdev.ko exposes below symbols for now, as we + * don't have a proper way to access parent ops directly yet. + * + * virtio_mdev_readl() + * virtio_mdev_writel() + */ +extern u32 virtio_mdev_readl(struct mdev_device *mdev, loff_t off); +extern void virtio_mdev_writel(struct mdev_device *mdev, loff_t off, u32 val); + +static u8 mdev_get_status(struct mdev_device *mdev) +{ + return virtio_mdev_readl(mdev, VIRTIO_MDEV_STATUS); +} + +static void mdev_set_status(struct mdev_device *mdev, u8 status) +{ + virtio_mdev_writel(mdev, VIRTIO_MDEV_STATUS, status); +} + +static void mdev_add_status(struct mdev_device *mdev, u8 status) +{ + status |= mdev_get_status(mdev); + mdev_set_status(mdev, status); +} + +static void mdev_reset(struct mdev_device *mdev) +{ + mdev_set_status(mdev, 0); +} + +static void handle_vq_kick(struct vhost_work *work) +{ + struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, + poll.work); + struct vhost_mdev *m = container_of(vq->dev, struct vhost_mdev, dev); + + virtio_mdev_writel(m->mdev, VIRTIO_MDEV_QUEUE_NOTIFY, vq - m->vqs); +} + +static long vhost_mdev_start_backend(struct vhost_mdev *m) +{ + struct mdev_device *mdev = m->mdev; + u64 features = m->acked_features; + u64 addr; + struct vhost_virtqueue *vq; + int queue_id; + + features |= 1ULL << VIRTIO_F_IOMMU_PLATFORM; + + virtio_mdev_writel(mdev, VIRTIO_MDEV_DRIVER_FEATURES_SEL, 1); + virtio_mdev_writel(mdev, VIRTIO_MDEV_DRIVER_FEATURES, + (u32)(features >> 32)); + + virtio_mdev_writel(mdev, VIRTIO_MDEV_DRIVER_FEATURES_SEL, 0); + virtio_mdev_writel(mdev, VIRTIO_MDEV_DRIVER_FEATURES, + (u32)features); + + mdev_add_status(mdev, VIRTIO_CONFIG_S_FEATURES_OK); + if (!(mdev_get_status(mdev) & VIRTIO_CONFIG_S_FEATURES_OK)) + return -ENODEV; + + for (queue_id = 0; queue_id < m->nvqs; queue_id++) { + vq = &m->vqs[queue_id]; + + if (!vq->desc || !vq->avail || !vq->used) + break; + + virtio_mdev_writel(mdev, VIRTIO_MDEV_QUEUE_NUM, vq->num); + + if (!vhost_translate_ring_addr(vq, (u64)vq->desc, + vhost_get_desc_size(vq, vq->num), + &addr)) + return -EINVAL; + + virtio_mdev_writel(mdev, VIRTIO_MDEV_QUEUE_DESC_LOW, addr); + virtio_mdev_writel(mdev, VIRTIO_MDEV_QUEUE_DESC_HIGH, + (addr >> 32)); + + if (!vhost_translate_ring_addr(vq, (u64)vq->avail, + vhost_get_avail_size(vq, vq->num), + &addr)) + return -EINVAL; + + virtio_mdev_writel(mdev, VIRTIO_MDEV_QUEUE_AVAIL_LOW, addr); + virtio_mdev_writel(mdev, VIRTIO_MDEV_QUEUE_AVAIL_HIGH, + (addr >> 32)); + + if (!vhost_translate_ring_addr(vq, (u64)vq->used, + vhost_get_used_size(vq, vq->num), + &addr)) + return -EINVAL; + + virtio_mdev_writel(mdev, VIRTIO_MDEV_QUEUE_USED_LOW, addr); + virtio_mdev_writel(mdev, VIRTIO_MDEV_QUEUE_USED_HIGH, + (addr >> 32)); + + // XXX: we need to support set_vring_base + + virtio_mdev_writel(mdev, VIRTIO_MDEV_QUEUE_READY, 1); + } + + // XXX: we need to setup interrupt as well + + mdev_add_status(mdev, VIRTIO_CONFIG_S_DRIVER_OK); + return 0; +} + +static long vhost_mdev_stop_backend(struct vhost_mdev *m) +{ + struct mdev_device *mdev = m->mdev; + + mdev_reset(mdev); + mdev_add_status(mdev, VIRTIO_CONFIG_S_ACKNOWLEDGE); + mdev_add_status(mdev, VIRTIO_CONFIG_S_DRIVER); + return 0; +} + +static long vhost_set_state(struct vhost_mdev *m, u64 __user *statep) +{ + u64 state; + long r; + + if (copy_from_user(&state, statep, sizeof(state))) + return -EFAULT; + + if (state >= VHOST_MDEV_S_MAX) + return -EINVAL; + + if (m->state == state) + return 0; + + m->state = state; + + switch (m->state) { + case VHOST_MDEV_S_RUNNING: + r = vhost_mdev_start_backend(m); + break; + case VHOST_MDEV_S_STOPPED: + r = vhost_mdev_stop_backend(m); + break; + default: + r = -EINVAL; + break; + } + + return r; +} + +static long vhost_get_features(struct vhost_mdev *m, u64 __user *featurep) +{ + if (copy_to_user(featurep, &m->features, sizeof(m->features))) + return -EFAULT; + return 0; +} + +static long vhost_set_features(struct vhost_mdev *m, u64 __user *featurep) +{ + u64 features; + + if (copy_from_user(&features, featurep, sizeof(features))) + return -EFAULT; + + if (features & ~m->features) + return -EINVAL; + + m->acked_features = features; + + return 0; +} + +static long vhost_get_vring_base(struct vhost_mdev *m, void __user *argp) +{ + struct vhost_virtqueue *vq; + u32 idx; + long r; + + r = get_user(idx, (u32 __user *)argp); + if (r < 0) + return r; + if (idx >= m->nvqs) + return -ENOBUFS; + + vq = &m->vqs[idx]; + + // XXX: we need to support get_vring_base + //vq->last_avail_idx = virtio_mdev_readl(b->mdev, ...); + + return vhost_vring_ioctl(&m->dev, VHOST_GET_VRING_BASE, argp); +} + +static void vhost_mdev_release_backend(struct vhost_mdev *m) +{ + if (!m->mdev) + return; + + if (m->state != VHOST_MDEV_S_STOPPED) { + m->state = VHOST_MDEV_S_STOPPED; + vhost_mdev_stop_backend(m); + } + + vhost_dev_stop(&m->dev); + vhost_dev_cleanup(&m->dev); + + kfree(m->dev.vqs); + kfree(m->vqs); + + vfio_device_put(m->vfio_device); + vfio_group_put_external_user(m->vfio_group); + + m->mdev = NULL; +} + +static long vhost_mdev_set_backend(struct vhost_mdev *m, + struct vhost_mdev_backend __user *argp) +{ + struct vhost_mdev_backend backend; + struct mdev_device *mdev; + struct vhost_dev *dev; + struct vhost_virtqueue **vqs; + struct file *file; + struct vfio_device *device; + struct vfio_group *group; + unsigned long magic; + u64 features; + int i, nvqs; + long r; + + vhost_mdev_release_backend(m); + + if (copy_from_user(&backend, argp, sizeof(backend))) { + r = -EFAULT; + goto err; + } + + file = fget(backend.group_fd); + if (!file) { + r = -EBADF; + goto err; + } + + group = vfio_group_get_external_user(file); + fput(file); + if (IS_ERR(group)) { + r = PTR_ERR(group); + goto err; + } + + device = vfio_device_get_from_fd(group, backend.device_fd); + if (!IS_ERR(device)) { + r = PTR_ERR(device); + goto err_put_group; + } + + if (!vfio_device_ops_match(device, &vfio_mdev_dev_ops)) { + r = -EINVAL; + goto err_put_device; + } + + mdev = vfio_device_data(m->vfio_device); + + magic = virtio_mdev_readl(mdev, VIRTIO_MDEV_MAGIC_VALUE); + if (magic != ('v' | 'i' << 8 | 'r' << 16 | 't' << 24)) { + r = -ENODEV; + goto err_put_device; + } + + mdev_reset(mdev); + mdev_add_status(mdev, VIRTIO_CONFIG_S_ACKNOWLEDGE); + mdev_add_status(mdev, VIRTIO_CONFIG_S_DRIVER); + + virtio_mdev_writel(mdev, VIRTIO_MDEV_DEVICE_FEATURES_SEL, 1); + features = virtio_mdev_readl(mdev, VIRTIO_MDEV_DEVICE_FEATURES); + features <<= 32; + + virtio_mdev_writel(mdev, VIRTIO_MDEV_DEVICE_FEATURES_SEL, 0); + features |= virtio_mdev_readl(mdev, VIRTIO_MDEV_DEVICE_FEATURES); + + if (!(features & (1ULL << VIRTIO_F_IOMMU_PLATFORM))) { + r = -EINVAL; + goto err_put_device; + } + + m->features = features; + + nvqs = virtio_mdev_readl(mdev, VIRTIO_MDEV_QUEUE_NUM_MAX); + m->nvqs = nvqs; + + m->vqs = kmalloc_array(nvqs, sizeof(struct vhost_virtqueue), + GFP_KERNEL); + if (!m->vqs) { + r = -ENOMEM; + goto err_put_device; + } + + vqs = kmalloc_array(nvqs, sizeof(*vqs), GFP_KERNEL); + if (!vqs) { + r = -ENOMEM; + goto err_free_vqs; + } + + dev = &m->dev; + for (i = 0; i < nvqs; i++) { + vqs[i] = &m->vqs[i]; + vqs[i]->handle_kick = handle_vq_kick; + } + vhost_dev_init(dev, vqs, nvqs, 0, 0, 0); + + m->vfio_group = group; + m->vfio_device = device; + m->mdev = mdev; + + return 0; + +err_free_vqs: + kfree(m->vqs); +err_put_device: + vfio_device_put(device); +err_put_group: + vfio_group_put_external_user(group); +err: + return r; +} + +static int vhost_mdev_open(struct inode *inode, struct file *f) +{ + struct vhost_mdev *m; + + m = kzalloc(sizeof(*m), GFP_KERNEL | __GFP_RETRY_MAYFAIL); + if (!m) + return -ENOMEM; + + mutex_init(&m->mutex); + f->private_data = m; + + return 0; +} + +static int vhost_mdev_release(struct inode *inode, struct file *f) +{ + struct vhost_mdev *m = f->private_data; + + vhost_mdev_release_backend(m); + mutex_destroy(&m->mutex); + kfree(m); + + return 0; +} + +static long vhost_mdev_ioctl(struct file *f, unsigned int cmd, + unsigned long arg) +{ + void __user *argp = (void __user *)arg; + struct vhost_mdev *m = f->private_data; + long r; + + mutex_lock(&m->mutex); + + if (cmd == VHOST_MDEV_SET_BACKEND) { + r = vhost_mdev_set_backend(m, argp); + goto done; + } + + if (!m->mdev) { + r = -EINVAL; + goto done; + } + + switch (cmd) { + case VHOST_MDEV_SET_STATE: + r = vhost_set_state(m, argp); + break; + case VHOST_GET_FEATURES: + r = vhost_get_features(m, argp); + break; + case VHOST_SET_FEATURES: + r = vhost_set_features(m, argp); + break; + case VHOST_GET_VRING_BASE: + r = vhost_get_vring_base(m, argp); + break; + default: + r = vhost_dev_ioctl(&m->dev, cmd, argp); + if (r == -ENOIOCTLCMD) + r = vhost_vring_ioctl(&m->dev, cmd, argp); + } + +done: + mutex_lock(&m->mutex); + return r; +} + +#ifdef CONFIG_COMPAT +static long vhost_mdev_compat_ioctl(struct file *f, unsigned int ioctl, + unsigned long arg) +{ + return vhost_mdev_ioctl(f, ioctl, (unsigned long)compat_ptr(arg)); +} +#endif + +static const struct file_operations vhost_mdev_fops = { + .owner = THIS_MODULE, + .release = vhost_mdev_release, + .unlocked_ioctl = vhost_mdev_ioctl, +#ifdef CONFIG_COMPAT + .compat_ioctl = vhost_mdev_compat_ioctl, +#endif + .open = vhost_mdev_open, + .llseek = noop_llseek, +}; + +static struct miscdevice vhost_mdev_misc = { + .minor = MISC_DYNAMIC_MINOR, + .name = "vhost-mdev", + .fops = &vhost_mdev_fops, +}; + +static int __init vhost_mdev_init(void) +{ + return misc_register(&vhost_mdev_misc); +} +module_init(vhost_mdev_init); + +static void __exit vhost_mdev_exit(void) +{ + misc_deregister(&vhost_mdev_misc); +} +module_exit(vhost_mdev_exit); + +MODULE_VERSION("0.0.0"); +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("Hardware vhost accelerator abstraction"); diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 5dc174ac8cac..0f7236a17a56 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -426,8 +426,7 @@ bool vhost_exceeds_weight(struct vhost_virtqueue *vq, } EXPORT_SYMBOL_GPL(vhost_exceeds_weight); -static size_t vhost_get_avail_size(struct vhost_virtqueue *vq, - unsigned int num) +size_t vhost_get_avail_size(struct vhost_virtqueue *vq, unsigned int num) { size_t event __maybe_unused = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0; @@ -435,9 +434,9 @@ static size_t vhost_get_avail_size(struct vhost_virtqueue *vq, return sizeof(*vq->avail) + sizeof(*vq->avail->ring) * num + event; } +EXPORT_SYMBOL_GPL(vhost_get_avail_size); -static size_t vhost_get_used_size(struct vhost_virtqueue *vq, - unsigned int num) +size_t vhost_get_used_size(struct vhost_virtqueue *vq, unsigned int num) { size_t event __maybe_unused = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0; @@ -445,12 +444,13 @@ static size_t vhost_get_used_size(struct vhost_virtqueue *vq, return sizeof(*vq->used) + sizeof(*vq->used->ring) * num + event; } +EXPORT_SYMBOL_GPL(vhost_get_used_size); -static size_t vhost_get_desc_size(struct vhost_virtqueue *vq, - unsigned int num) +size_t vhost_get_desc_size(struct vhost_virtqueue *vq, unsigned int num) { return sizeof(*vq->desc) * num; } +EXPORT_SYMBOL_GPL(vhost_get_desc_size); void vhost_dev_init(struct vhost_dev *dev, struct vhost_virtqueue **vqs, int nvqs, @@ -2617,6 +2617,33 @@ struct vhost_msg_node *vhost_dequeue_msg(struct vhost_dev *dev, } EXPORT_SYMBOL_GPL(vhost_dequeue_msg); +bool vhost_translate_ring_addr(struct vhost_virtqueue *vq, u64 ring_addr, + u64 len, u64 *addr) +{ + struct vhost_umem *umem = vq->umem; + struct vhost_umem_node *u; + + if (vhost_overflow(ring_addr, len)) + return false; + + if (vq->iotlb) { + /* Ring address is already IOVA */ + *addr = ring_addr; + return true; + } + + /* Ring address is host virtual address. */ + list_for_each_entry(u, &umem->umem_list, link) { + if (u->userspace_addr <= ring_addr && + u->userspace_addr + u->size >= ring_addr + len) { + *addr = ring_addr - u->userspace_addr + u->start; + return true; + } + } + + return false; +} +EXPORT_SYMBOL_GPL(vhost_translate_ring_addr); static int __init vhost_init(void) { diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index e9ed2722b633..294a6bcb6adf 100644 --- a/drivers/vhost/vhost.h +++ b/drivers/vhost/vhost.h @@ -189,6 +189,12 @@ long vhost_dev_ioctl(struct vhost_dev *, unsigned int ioctl, void __user *argp); long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp); bool vhost_vq_access_ok(struct vhost_virtqueue *vq); bool vhost_log_access_ok(struct vhost_dev *); +bool vhost_translate_ring_addr(struct vhost_virtqueue *vq, u64 ring_addr, + u64 len, u64 *addr); + +size_t vhost_get_avail_size(struct vhost_virtqueue *vq, unsigned int num); +size_t vhost_get_used_size(struct vhost_virtqueue *vq, unsigned int num); +size_t vhost_get_desc_size(struct vhost_virtqueue *vq, unsigned int num); int vhost_get_vq_desc(struct vhost_virtqueue *, struct iovec iov[], unsigned int iov_count, diff --git a/include/uapi/linux/vhost.h b/include/uapi/linux/vhost.h index 40d028eed645..7213aedc8506 100644 --- a/include/uapi/linux/vhost.h +++ b/include/uapi/linux/vhost.h @@ -116,4 +116,14 @@ #define VHOST_VSOCK_SET_GUEST_CID _IOW(VHOST_VIRTIO, 0x60, __u64) #define VHOST_VSOCK_SET_RUNNING _IOW(VHOST_VIRTIO, 0x61, int) +/* VHOST_MDEV specific defines */ + +#define VHOST_MDEV_SET_BACKEND _IOW(VHOST_VIRTIO, 0x70, \ + struct vhost_mdev_backend) +#define VHOST_MDEV_SET_STATE _IOW(VHOST_VIRTIO, 0x71, __u64) + +#define VHOST_MDEV_S_STOPPED 0 +#define VHOST_MDEV_S_RUNNING 1 +#define VHOST_MDEV_S_MAX 2 + #endif diff --git a/include/uapi/linux/vhost_types.h b/include/uapi/linux/vhost_types.h index c907290ff065..f06f0dbb7e51 100644 --- a/include/uapi/linux/vhost_types.h +++ b/include/uapi/linux/vhost_types.h @@ -119,6 +119,11 @@ struct vhost_scsi_target { unsigned short reserved; }; +struct vhost_mdev_backend { + int group_fd; + int device_fd; +}; + /* Feature bits */ /* Log all write descriptors. Can be changed while device is active. */ #define VHOST_F_LOG_ALL 26