On Wed, May 11, 2022 at 2:32 PM Stefano Garzarella <sgarz...@redhat.com> wrote:
>
> On Wed, May 11, 2022 at 10:56:02AM +0800, Jason Wang wrote:
> >On Tue, May 10, 2022 at 8:59 PM Longpeng(Mike) <longpe...@huawei.com> wrote:
> >>
> >> From: Longpeng <longpe...@huawei.com>
> >>
> >> Supports vdpa-dev.
> >>
> >> Signed-off-by: Longpeng <longpe...@huawei.com>
> >> ---
> >> hw/virtio/Kconfig | 5 +
> >> hw/virtio/meson.build | 1 +
> >> hw/virtio/vdpa-dev.c | 385 +++++++++++++++++++++++++++++++++++
> >> include/hw/virtio/vdpa-dev.h | 43 ++++
> >> 4 files changed, 434 insertions(+)
> >> create mode 100644 hw/virtio/vdpa-dev.c
> >> create mode 100644 include/hw/virtio/vdpa-dev.h
> >>
> >> diff --git a/hw/virtio/Kconfig b/hw/virtio/Kconfig
> >> index c144d42f9b..2723283382 100644
> >> --- a/hw/virtio/Kconfig
> >> +++ b/hw/virtio/Kconfig
> >> @@ -68,3 +68,8 @@ config VHOST_USER_RNG
> >> bool
> >> default y
> >> depends on VIRTIO && VHOST_USER
> >> +
> >> +config VHOST_VDPA_DEV
> >> + bool
> >> + default y if VIRTIO_PCI
> >
> >Do we have the plan to add VIRTIO_MMIO support?
> >
> >> + depends on VIRTIO && VHOST_VDPA && LINUX
> >> diff --git a/hw/virtio/meson.build b/hw/virtio/meson.build
> >> index 67dc77e00f..8f6f86db71 100644
> >> --- a/hw/virtio/meson.build
> >> +++ b/hw/virtio/meson.build
> >> @@ -29,6 +29,7 @@ virtio_ss.add(when: 'CONFIG_VHOST_USER_I2C', if_true:
> >> files('vhost-user-i2c.c'))
> >> virtio_ss.add(when: ['CONFIG_VIRTIO_PCI', 'CONFIG_VHOST_USER_I2C'],
> >> if_true: files('vhost-user-i2c-pci.c'))
> >> virtio_ss.add(when: 'CONFIG_VHOST_USER_RNG', if_true:
> >> files('vhost-user-rng.c'))
> >> virtio_ss.add(when: ['CONFIG_VHOST_USER_RNG', 'CONFIG_VIRTIO_PCI'],
> >> if_true: files('vhost-user-rng-pci.c'))
> >> +virtio_ss.add(when: 'CONFIG_VHOST_VDPA_DEV', if_true: files('vdpa-dev.c'))
> >>
> >> virtio_pci_ss = ss.source_set()
> >> virtio_pci_ss.add(when: 'CONFIG_VHOST_VSOCK', if_true:
> >> files('vhost-vsock-pci.c'))
> >> diff --git a/hw/virtio/vdpa-dev.c b/hw/virtio/vdpa-dev.c
> >> new file mode 100644
> >> index 0000000000..543b5b4b81
> >> --- /dev/null
> >> +++ b/hw/virtio/vdpa-dev.c
> >> @@ -0,0 +1,385 @@
> >> +/*
> >> + * Vhost Vdpa Device
> >> + *
> >> + * Copyright (c) Huawei Technologies Co., Ltd. 2022. All Rights Reserved.
> >> + *
> >> + * Authors:
> >> + * Longpeng <longpe...@huawei.com>
> >> + *
> >> + * Largely based on the "vhost-user-blk-pci.c" and "vhost-user-blk.c"
> >> implemented by:
> >> + * Changpeng Liu <changpeng....@intel.com>
> >> + *
> >> + * This work is licensed under the terms of the GNU LGPL, version 2 or
> >> later.
> >> + * See the COPYING.LIB file in the top-level directory.
> >> + */
> >> +#include "qemu/osdep.h"
> >> +#include <sys/ioctl.h>
> >> +#include <linux/vhost.h>
> >> +#include "qapi/error.h"
> >> +#include "qemu/error-report.h"
> >> +#include "qemu/cutils.h"
> >> +#include "hw/qdev-core.h"
> >> +#include "hw/qdev-properties.h"
> >> +#include "hw/qdev-properties-system.h"
> >> +#include "hw/virtio/vhost.h"
> >> +#include "hw/virtio/virtio.h"
> >> +#include "hw/virtio/virtio-bus.h"
> >> +#include "hw/virtio/virtio-access.h"
> >> +#include "hw/virtio/vdpa-dev.h"
> >> +#include "sysemu/sysemu.h"
> >> +#include "sysemu/runstate.h"
> >> +
> >> +static void
> >> +vhost_vdpa_device_dummy_handle_output(VirtIODevice *vdev, VirtQueue *vq)
> >> +{
> >> + /* Nothing to do */
> >> +}
> >> +
> >> +static uint32_t
> >> +vhost_vdpa_device_get_u32(int fd, unsigned long int cmd, Error **errp)
> >> +{
> >> + uint32_t val = (uint32_t)-1;
> >> +
> >> + if (ioctl(fd, cmd, &val) < 0) {
> >> + error_setg(errp, "vhost-vdpa-device: cmd 0x%lx failed: %s",
> >> + cmd, strerror(errno));
> >> + }
> >> +
> >> + return val;
> >> +}
> >> +
> >> +static void vhost_vdpa_device_realize(DeviceState *dev, Error **errp)
> >> +{
> >> + VirtIODevice *vdev = VIRTIO_DEVICE(dev);
> >> + VhostVdpaDevice *v = VHOST_VDPA_DEVICE(vdev);
> >> + uint16_t max_queue_size;
> >> + struct vhost_virtqueue *vqs;
> >> + int i, ret;
> >> +
> >> + if (!v->vhostdev && v->vhostfd == -1) {
> >> + error_setg(errp, "both vhostdev and vhostfd are missing");
> >> + return;
> >> + }
> >> +
> >> + if (v->vhostdev && v->vhostfd != -1) {
> >> + error_setg(errp, "both vhostdev and vhostfd are set");
> >> + return;
> >> + }
> >> +
> >> + if (v->vhostfd == -1) {
> >> + v->vhostfd = qemu_open(v->vhostdev, O_RDWR, errp);
> >> + if (*errp) {
> >
> >Is this better to set error messages for all the possible failures
> >during realization?
> >
> >> + return;
> >> + }
> >> + }
> >> + v->vdpa.device_fd = v->vhostfd;
> >> +
> >> + v->vdev_id = vhost_vdpa_device_get_u32(v->vhostfd,
> >> + VHOST_VDPA_GET_DEVICE_ID,
> >> errp);
> >> + if (*errp) {
> >> + goto out;
> >> + }
> >> +
> >> + max_queue_size = vhost_vdpa_device_get_u32(v->vhostfd,
> >> + VHOST_VDPA_GET_VRING_NUM,
> >> errp);
> >> + if (*errp) {
> >> + goto out;
> >> + }
> >> +
> >> + if (v->queue_size > max_queue_size) {
> >> + error_setg(errp, "vhost-vdpa-device: invalid queue_size: %u
> >> (max:%u)",
> >> + v->queue_size, max_queue_size);
> >> + goto out;
> >> + } else if (!v->queue_size) {
> >> + v->queue_size = max_queue_size;
> >> + }
> >> +
> >> + v->num_queues = vhost_vdpa_device_get_u32(v->vhostfd,
> >> + VHOST_VDPA_GET_VQS_COUNT,
> >> errp);
> >> + if (*errp) {
> >> + goto out;
> >> + }
> >> +
> >> + if (!v->num_queues || v->num_queues > VIRTIO_QUEUE_MAX) {
> >> + error_setg(errp, "invalid number of virtqueues: %u (max:%u)",
> >> + v->num_queues, VIRTIO_QUEUE_MAX);
> >> + goto out;
> >> + }
> >> +
> >> + v->dev.nvqs = v->num_queues;
> >> + vqs = g_new0(struct vhost_virtqueue, v->dev.nvqs);
> >> + v->dev.vqs = vqs;
> >> + v->dev.vq_index = 0;
> >> + v->dev.vq_index_end = v->dev.nvqs;
> >> + v->dev.backend_features = 0;
> >> + v->started = false;
> >> +
> >> + ret = vhost_dev_init(&v->dev, &v->vdpa, VHOST_BACKEND_TYPE_VDPA, 0,
> >> NULL);
> >> + if (ret < 0) {
> >> + error_setg(errp, "vhost-vdpa-device: vhost initialization failed:
> >> %s",
> >> + strerror(-ret));
> >> + goto free_vqs;
> >> + }
> >> +
> >> + v->config_size = vhost_vdpa_device_get_u32(v->vhostfd,
> >> +
> >> VHOST_VDPA_GET_CONFIG_SIZE, errp);
> >> + if (*errp) {
> >> + goto vhost_cleanup;
> >> + }
> >> +
> >> + if (v->post_init && v->post_init(v, errp) < 0) {
> >> + goto free_virtio;
> >> + }
> >> +
> >> + v->config = g_malloc0(v->config_size);
> >> +
> >> + ret = vhost_dev_get_config(&v->dev, v->config, v->config_size, NULL);
> >> + if (ret < 0) {
> >> + error_setg(errp, "vhost-vdpa-device: get config failed");
> >> + goto free_config;
> >> + }
> >> +
> >> + virtio_init(vdev, "vhost-vdpa", v->vdev_id, v->config_size);
> >> +
> >> + v->virtqs = g_new0(VirtQueue *, v->dev.nvqs);
> >> + for (i = 0; i < v->dev.nvqs; i++) {
> >> + v->virtqs[i] = virtio_add_queue(vdev, v->queue_size,
> >> +
> >> vhost_vdpa_device_dummy_handle_output);
> >> + }
> >> +
> >> + return;
> >> +
> >> +free_virtio:
> >> + for (i = 0; i < v->num_queues; i++) {
> >> + virtio_delete_queue(v->virtqs[i]);
> >> + }
> >> + g_free(v->virtqs);
> >> + virtio_cleanup(vdev);
> >> +free_config:
> >> + g_free(v->config);
> >> +vhost_cleanup:
> >> + vhost_dev_cleanup(&v->dev);
> >> +free_vqs:
> >> + g_free(vqs);
> >> +out:
> >> + qemu_close(v->vhostfd);
> >> + v->vhostfd = -1;
> >> +}
> >> +
> >> +static void vhost_vdpa_device_unrealize(DeviceState *dev)
> >> +{
> >> + VirtIODevice *vdev = VIRTIO_DEVICE(dev);
> >> + VhostVdpaDevice *s = VHOST_VDPA_DEVICE(vdev);
> >> + int i;
> >> +
> >> + virtio_set_status(vdev, 0);
> >> +
> >> + for (i = 0; i < s->num_queues; i++) {
> >> + virtio_delete_queue(s->virtqs[i]);
> >> + }
> >> + g_free(s->virtqs);
> >> + virtio_cleanup(vdev);
> >> +
> >> + g_free(s->config);
> >> + g_free(s->dev.vqs);
> >> + vhost_dev_cleanup(&s->dev);
> >> + qemu_close(s->vhostfd);
> >> + s->vhostfd = -1;
> >> +}
> >> +
> >> +static void
> >> +vhost_vdpa_device_get_config(VirtIODevice *vdev, uint8_t *config)
> >> +{
> >> + VhostVdpaDevice *s = VHOST_VDPA_DEVICE(vdev);
> >> +
> >> + memcpy(config, s->config, s->config_size);
> >> +}
> >> +
> >> +static void
> >> +vhost_vdpa_device_set_config(VirtIODevice *vdev, const uint8_t *config)
> >> +{
> >> + VhostVdpaDevice *s = VHOST_VDPA_DEVICE(vdev);
> >> + int ret;
> >> +
> >> + ret = vhost_dev_set_config(&s->dev, s->config, 0, s->config_size,
> >> + VHOST_SET_CONFIG_TYPE_MASTER);
> >> + if (ret) {
> >> + error_report("set device config space failed");
> >> + return;
> >> + }
> >> +}
> >> +
> >> +static uint64_t vhost_vdpa_device_get_features(VirtIODevice *vdev,
> >> + uint64_t features,
> >> + Error **errp)
> >> +{
> >> + VhostVdpaDevice *s = VHOST_VDPA_DEVICE(vdev);
> >> + uint64_t backend_features = s->dev.features;
> >> +
> >> + if (!virtio_has_feature(features, VIRTIO_F_IOMMU_PLATFORM)) {
> >> + virtio_clear_feature(&backend_features, VIRTIO_F_IOMMU_PLATFORM);
> >> + }
> >> +
> >> + return backend_features;
> >> +}
> >> +
> >> +static int vhost_vdpa_device_start(VirtIODevice *vdev, Error **errp)
> >> +{
> >> + VhostVdpaDevice *s = VHOST_VDPA_DEVICE(vdev);
> >> + BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
> >> + VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
> >> + int i, ret;
> >> +
> >> + if (!k->set_guest_notifiers) {
> >> + error_setg(errp, "binding does not support guest notifiers");
> >> + return -ENOSYS;
> >> + }
> >> +
> >> + ret = vhost_dev_enable_notifiers(&s->dev, vdev);
> >> + if (ret < 0) {
> >> + error_setg_errno(errp, -ret, "Error enabling host notifiers");
> >> + return ret;
> >> + }
> >> +
> >> + ret = k->set_guest_notifiers(qbus->parent, s->dev.nvqs, true);
> >> + if (ret < 0) {
> >> + error_setg_errno(errp, -ret, "Error binding guest notifier");
> >> + goto err_host_notifiers;
> >> + }
> >> +
> >> + s->dev.acked_features = vdev->guest_features;
> >> +
> >> + ret = vhost_dev_start(&s->dev, vdev);
> >> + if (ret < 0) {
> >> + error_setg_errno(errp, -ret, "Error starting vhost");
> >> + goto err_guest_notifiers;
> >> + }
> >> + s->started = true;
> >> +
> >> + /*
> >> + * guest_notifier_mask/pending not used yet, so just unmask
> >> + * everything here. virtio-pci will do the right thing by
> >> + * enabling/disabling irqfd.
> >> + */
> >> + for (i = 0; i < s->dev.nvqs; i++) {
> >> + vhost_virtqueue_mask(&s->dev, vdev, i, false);
> >> + }
> >> +
> >> + return ret;
> >> +
> >> +err_guest_notifiers:
> >> + k->set_guest_notifiers(qbus->parent, s->dev.nvqs, false);
> >> +err_host_notifiers:
> >> + vhost_dev_disable_notifiers(&s->dev, vdev);
> >> + return ret;
> >> +}
> >> +
> >> +static void vhost_vdpa_device_stop(VirtIODevice *vdev)
> >> +{
> >> + VhostVdpaDevice *s = VHOST_VDPA_DEVICE(vdev);
> >> + BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
> >> + VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
> >> + int ret;
> >> +
> >> + if (!s->started) {
> >> + return;
> >> + }
> >> + s->started = false;
> >> +
> >> + if (!k->set_guest_notifiers) {
> >> + return;
> >> + }
> >> +
> >> + vhost_dev_stop(&s->dev, vdev);
> >> +
> >> + ret = k->set_guest_notifiers(qbus->parent, s->dev.nvqs, false);
> >> + if (ret < 0) {
> >> + error_report("vhost guest notifier cleanup failed: %d", ret);
> >> + return;
> >> + }
> >> +
> >> + vhost_dev_disable_notifiers(&s->dev, vdev);
> >> +}
> >> +
> >> +static void vhost_vdpa_device_set_status(VirtIODevice *vdev, uint8_t
> >> status)
> >> +{
> >> + VhostVdpaDevice *s = VHOST_VDPA_DEVICE(vdev);
> >> + bool should_start = virtio_device_started(vdev, status);
> >> + Error *local_err = NULL;
> >> + int ret;
> >> +
> >> + if (!vdev->vm_running) {
> >> + should_start = false;
> >> + }
> >> +
> >> + if (s->started == should_start) {
> >> + return;
> >> + }
> >> +
> >> + if (should_start) {
> >> + ret = vhost_vdpa_device_start(vdev, &local_err);
> >> + if (ret < 0) {
> >> + error_reportf_err(local_err, "vhost-vdpa-device: start
> >> failed: ");
> >> + }
> >> + } else {
> >> + vhost_vdpa_device_stop(vdev);
> >> + }
> >> +}
> >> +
> >> +static Property vhost_vdpa_device_properties[] = {
> >> + DEFINE_PROP_STRING("vhostdev", VhostVdpaDevice, vhostdev),
> >> + DEFINE_PROP_INT32("vhostfd", VhostVdpaDevice, vhostfd, -1),
> >
> >This is probably not needed since we can "abuse" /dev/fd/X for
> >vhostdev.
>
> IIRC for other vhost devices (e.g. vhost-vsock) the management layer
> (e.g. libvirt) opens the device (because I think QEMU has less
> permissions) and then passes the fd to QEMU, could this be useful for
> this scenario as well?
Yes, it's the way current vhost-vDPA did (the fd is passing via SCM_RIGHTS).
Thanks
>
> Thanks,
> Stefano
>
