[Virtio-fs] [PATCH v2 09/13] hw/virtio: derive vhost-user-rng from vhost-user-device
Mark Cave-Ayland
mark.cave-ayland at ilande.co.uk
Thu Apr 20 10:09:07 UTC 2023
On 18/04/2023 17:21, Alex Bennée wrote:
> Now we can take advantage of our new base class and make
> vhost-user-rng a much simpler boilerplate wrapper. Also as this
> doesn't require any target specific hacks we only need to build the
> stubs once.
>
> Signed-off-by: Alex Bennée <alex.bennee at linaro.org>
>
> ---
> v2
> - new derivation layout
> - move directly to softmmu_virtio_ss
> ---
> include/hw/virtio/vhost-user-rng.h | 11 +-
> hw/virtio/vhost-user-rng.c | 277 +++--------------------------
> hw/virtio/meson.build | 7 +-
> 3 files changed, 28 insertions(+), 267 deletions(-)
>
> diff --git a/include/hw/virtio/vhost-user-rng.h b/include/hw/virtio/vhost-user-rng.h
> index ddd9f01eea..13139c0d9d 100644
> --- a/include/hw/virtio/vhost-user-rng.h
> +++ b/include/hw/virtio/vhost-user-rng.h
> @@ -12,21 +12,14 @@
> #include "hw/virtio/virtio.h"
> #include "hw/virtio/vhost.h"
> #include "hw/virtio/vhost-user.h"
> -#include "chardev/char-fe.h"
> +#include "hw/virtio/vhost-user-device.h"
>
> #define TYPE_VHOST_USER_RNG "vhost-user-rng"
> OBJECT_DECLARE_SIMPLE_TYPE(VHostUserRNG, VHOST_USER_RNG)
>
> struct VHostUserRNG {
> /*< private >*/
> - VirtIODevice parent;
> - CharBackend chardev;
> - struct vhost_virtqueue *vhost_vq;
> - struct vhost_dev vhost_dev;
> - VhostUserState vhost_user;
> - VirtQueue *req_vq;
> - bool connected;
> -
> + VHostUserBase parent;
> /*< public >*/
> };
>
> diff --git a/hw/virtio/vhost-user-rng.c b/hw/virtio/vhost-user-rng.c
> index efc54cd3fb..71d3991f93 100644
> --- a/hw/virtio/vhost-user-rng.c
> +++ b/hw/virtio/vhost-user-rng.c
> @@ -3,7 +3,7 @@
> *
> * Copyright (c) 2021 Mathieu Poirier <mathieu.poirier at linaro.org>
> *
> - * Implementation seriously tailored on vhost-user-i2c.c
> + * Simple wrapper of the generic vhost-user-device.
> *
> * SPDX-License-Identifier: GPL-2.0-or-later
> */
> @@ -13,281 +13,46 @@
> #include "hw/qdev-properties.h"
> #include "hw/virtio/virtio-bus.h"
> #include "hw/virtio/vhost-user-rng.h"
> -#include "qemu/error-report.h"
> #include "standard-headers/linux/virtio_ids.h"
>
> -static const int feature_bits[] = {
> - VIRTIO_F_RING_RESET,
> - VHOST_INVALID_FEATURE_BIT
> -};
> -
> -static void vu_rng_start(VirtIODevice *vdev)
> -{
> - VHostUserRNG *rng = VHOST_USER_RNG(vdev);
> - BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
> - VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
> - int ret;
> - int i;
> -
> - if (!k->set_guest_notifiers) {
> - error_report("binding does not support guest notifiers");
> - return;
> - }
> -
> - ret = vhost_dev_enable_notifiers(&rng->vhost_dev, vdev);
> - if (ret < 0) {
> - error_report("Error enabling host notifiers: %d", -ret);
> - return;
> - }
> -
> - ret = k->set_guest_notifiers(qbus->parent, rng->vhost_dev.nvqs, true);
> - if (ret < 0) {
> - error_report("Error binding guest notifier: %d", -ret);
> - goto err_host_notifiers;
> - }
> -
> - rng->vhost_dev.acked_features = vdev->guest_features;
> - ret = vhost_dev_start(&rng->vhost_dev, vdev, true);
> - if (ret < 0) {
> - error_report("Error starting vhost-user-rng: %d", -ret);
> - goto err_guest_notifiers;
> - }
> -
> - /*
> - * 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 < rng->vhost_dev.nvqs; i++) {
> - vhost_virtqueue_mask(&rng->vhost_dev, vdev, i, false);
> - }
> -
> - return;
> -
> -err_guest_notifiers:
> - k->set_guest_notifiers(qbus->parent, rng->vhost_dev.nvqs, false);
> -err_host_notifiers:
> - vhost_dev_disable_notifiers(&rng->vhost_dev, vdev);
> -}
> -
> -static void vu_rng_stop(VirtIODevice *vdev)
> -{
> - VHostUserRNG *rng = VHOST_USER_RNG(vdev);
> - BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
> - VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
> - int ret;
> -
> - if (!k->set_guest_notifiers) {
> - return;
> - }
> -
> - vhost_dev_stop(&rng->vhost_dev, vdev, true);
> -
> - ret = k->set_guest_notifiers(qbus->parent, rng->vhost_dev.nvqs, false);
> - if (ret < 0) {
> - error_report("vhost guest notifier cleanup failed: %d", ret);
> - return;
> - }
> -
> - vhost_dev_disable_notifiers(&rng->vhost_dev, vdev);
> -}
> -
> -static void vu_rng_set_status(VirtIODevice *vdev, uint8_t status)
> -{
> - VHostUserRNG *rng = VHOST_USER_RNG(vdev);
> - bool should_start = virtio_device_should_start(vdev, status);
> -
> - if (vhost_dev_is_started(&rng->vhost_dev) == should_start) {
> - return;
> - }
> -
> - if (should_start) {
> - vu_rng_start(vdev);
> - } else {
> - vu_rng_stop(vdev);
> - }
> -}
> -
> -static uint64_t vu_rng_get_features(VirtIODevice *vdev,
> - uint64_t requested_features, Error **errp)
> -{
> - VHostUserRNG *rng = VHOST_USER_RNG(vdev);
> -
> - return vhost_get_features(&rng->vhost_dev, feature_bits,
> - requested_features);
> -}
> -
> -static void vu_rng_handle_output(VirtIODevice *vdev, VirtQueue *vq)
> -{
> - /*
> - * Not normally called; it's the daemon that handles the queue;
> - * however virtio's cleanup path can call this.
> - */
> -}
> -
> -static void vu_rng_guest_notifier_mask(VirtIODevice *vdev, int idx, bool mask)
> -{
> - VHostUserRNG *rng = VHOST_USER_RNG(vdev);
> -
> - vhost_virtqueue_mask(&rng->vhost_dev, vdev, idx, mask);
> -}
> -
> -static bool vu_rng_guest_notifier_pending(VirtIODevice *vdev, int idx)
> -{
> - VHostUserRNG *rng = VHOST_USER_RNG(vdev);
> -
> - return vhost_virtqueue_pending(&rng->vhost_dev, idx);
> -}
> -
> -static void vu_rng_connect(DeviceState *dev)
> -{
> - VirtIODevice *vdev = VIRTIO_DEVICE(dev);
> - VHostUserRNG *rng = VHOST_USER_RNG(vdev);
> -
> - if (rng->connected) {
> - return;
> - }
> -
> - rng->connected = true;
> -
> - /* restore vhost state */
> - if (virtio_device_started(vdev, vdev->status)) {
> - vu_rng_start(vdev);
> - }
> -}
> -
> -static void vu_rng_disconnect(DeviceState *dev)
> -{
> - VirtIODevice *vdev = VIRTIO_DEVICE(dev);
> - VHostUserRNG *rng = VHOST_USER_RNG(vdev);
> -
> - if (!rng->connected) {
> - return;
> - }
> -
> - rng->connected = false;
> -
> - if (vhost_dev_is_started(&rng->vhost_dev)) {
> - vu_rng_stop(vdev);
> - }
> -}
> -
> -static void vu_rng_event(void *opaque, QEMUChrEvent event)
> -{
> - DeviceState *dev = opaque;
> -
> - switch (event) {
> - case CHR_EVENT_OPENED:
> - vu_rng_connect(dev);
> - break;
> - case CHR_EVENT_CLOSED:
> - vu_rng_disconnect(dev);
> - break;
> - case CHR_EVENT_BREAK:
> - case CHR_EVENT_MUX_IN:
> - case CHR_EVENT_MUX_OUT:
> - /* Ignore */
> - break;
> - }
> -}
> -
> -static void vu_rng_device_realize(DeviceState *dev, Error **errp)
> -{
> - VirtIODevice *vdev = VIRTIO_DEVICE(dev);
> - VHostUserRNG *rng = VHOST_USER_RNG(dev);
> - int ret;
> -
> - if (!rng->chardev.chr) {
> - error_setg(errp, "missing chardev");
> - return;
> - }
> -
> - if (!vhost_user_init(&rng->vhost_user, &rng->chardev, errp)) {
> - return;
> - }
> -
> - virtio_init(vdev, VIRTIO_ID_RNG, 0);
> -
> - rng->req_vq = virtio_add_queue(vdev, 4, vu_rng_handle_output);
> - if (!rng->req_vq) {
> - error_setg_errno(errp, -1, "virtio_add_queue() failed");
> - goto virtio_add_queue_failed;
> - }
> -
> - rng->vhost_dev.nvqs = 1;
> - rng->vhost_dev.vqs = g_new0(struct vhost_virtqueue, rng->vhost_dev.nvqs);
> - ret = vhost_dev_init(&rng->vhost_dev, &rng->vhost_user,
> - VHOST_BACKEND_TYPE_USER, 0, errp);
> - if (ret < 0) {
> - error_setg_errno(errp, -ret, "vhost_dev_init() failed");
> - goto vhost_dev_init_failed;
> - }
> -
> - qemu_chr_fe_set_handlers(&rng->chardev, NULL, NULL, vu_rng_event, NULL,
> - dev, NULL, true);
> -
> - return;
> -
> -vhost_dev_init_failed:
> - g_free(rng->vhost_dev.vqs);
> - virtio_delete_queue(rng->req_vq);
> -virtio_add_queue_failed:
> - virtio_cleanup(vdev);
> - vhost_user_cleanup(&rng->vhost_user);
> -}
> -
> -static void vu_rng_device_unrealize(DeviceState *dev)
> -{
> - VirtIODevice *vdev = VIRTIO_DEVICE(dev);
> - VHostUserRNG *rng = VHOST_USER_RNG(dev);
> - struct vhost_virtqueue *vhost_vqs = rng->vhost_dev.vqs;
> -
> - vu_rng_set_status(vdev, 0);
> -
> - vhost_dev_cleanup(&rng->vhost_dev);
> - g_free(vhost_vqs);
> - virtio_delete_queue(rng->req_vq);
> - virtio_cleanup(vdev);
> - vhost_user_cleanup(&rng->vhost_user);
> -}
> -
> -static struct vhost_dev *vu_rng_get_vhost(VirtIODevice *vdev)
> -{
> - VHostUserRNG *rng = VHOST_USER_RNG(vdev);
> - return &rng->vhost_dev;
> -}
> -
> static const VMStateDescription vu_rng_vmstate = {
> .name = "vhost-user-rng",
> .unmigratable = 1,
> };
>
> -static Property vu_rng_properties[] = {
> - DEFINE_PROP_CHR("chardev", VHostUserRNG, chardev),
> +static Property vrng_properties[] = {
> + DEFINE_PROP_CHR("chardev", VHostUserBase, chardev),
I did a double-take that this wouldn't have to be VHostUserRNG, but I think it should
still work with the new object hierarchy.
> DEFINE_PROP_END_OF_LIST(),
> };
>
> +static void vu_rng_base_realize(DeviceState *dev, Error **errp)
> +{
> + VHostUserBase *vub = VHOST_USER_BASE(dev);
> + VHostUserBaseClass *vubs = VHOST_USER_BASE_GET_CLASS(dev);
> +
> + /* Fixed for RNG */
> + vub->virtio_id = VIRTIO_ID_RNG;
> + vub->num_vqs = 1;
> +
> + vubs->parent_realize(dev, errp);
> +}
> +
> static void vu_rng_class_init(ObjectClass *klass, void *data)
> {
> DeviceClass *dc = DEVICE_CLASS(klass);
> - VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
> + VHostUserBaseClass *vubc = VHOST_USER_BASE_CLASS(klass);
>
> - device_class_set_props(dc, vu_rng_properties);
> dc->vmsd = &vu_rng_vmstate;
> - set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
> + device_class_set_props(dc, vrng_properties);
> + device_class_set_parent_realize(dc, vu_rng_base_realize,
> + &vubc->parent_realize);
>
> - vdc->realize = vu_rng_device_realize;
> - vdc->unrealize = vu_rng_device_unrealize;
> - vdc->get_features = vu_rng_get_features;
> - vdc->set_status = vu_rng_set_status;
> - vdc->guest_notifier_mask = vu_rng_guest_notifier_mask;
> - vdc->guest_notifier_pending = vu_rng_guest_notifier_pending;
> - vdc->get_vhost = vu_rng_get_vhost;
> + set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
> }
>
> static const TypeInfo vu_rng_info = {
> .name = TYPE_VHOST_USER_RNG,
> - .parent = TYPE_VIRTIO_DEVICE,
> + .parent = TYPE_VHOST_USER_BASE,
> .instance_size = sizeof(VHostUserRNG),
> .class_init = vu_rng_class_init,
> };
> diff --git a/hw/virtio/meson.build b/hw/virtio/meson.build
> index c0a86b94ae..de442dcb96 100644
> --- a/hw/virtio/meson.build
> +++ b/hw/virtio/meson.build
> @@ -3,6 +3,11 @@ softmmu_virtio_ss.add(files('virtio-bus.c'))
> softmmu_virtio_ss.add(when: 'CONFIG_VIRTIO_PCI', if_true: files('virtio-pci.c'))
> softmmu_virtio_ss.add(when: 'CONFIG_VIRTIO_MMIO', if_true: files('virtio-mmio.c'))
>
> +# VirtIO stubs which don't need building per-guest
> +softmmu_virtio_ss.add(when: 'CONFIG_VHOST_USER_RNG', if_true: files('vhost-user-rng.c'))
> +softmmu_virtio_ss.add(when: ['CONFIG_VIRTIO_PCI', 'CONFIG_VHOST_USER_RNG'],
> + if_true: files('vhost-user-rng-pci.c'))
> +
> specific_virtio_ss = ss.source_set()
> specific_virtio_ss.add(files('virtio.c'))
> specific_virtio_ss.add(files('virtio-config-io.c', 'virtio-qmp.c'))
> @@ -32,7 +37,6 @@ specific_virtio_ss.add(when: 'CONFIG_VIRTIO_RNG', if_true: files('virtio-rng.c')
> specific_virtio_ss.add(when: 'CONFIG_VIRTIO_IOMMU', if_true: files('virtio-iommu.c'))
> specific_virtio_ss.add(when: 'CONFIG_VIRTIO_MEM', if_true: files('virtio-mem.c'))
> specific_virtio_ss.add(when: 'CONFIG_VHOST_USER_I2C', if_true: files('vhost-user-i2c.c'))
> -specific_virtio_ss.add(when: 'CONFIG_VHOST_USER_RNG', if_true: files('vhost-user-rng.c'))
> specific_virtio_ss.add(when: 'CONFIG_VHOST_USER_GPIO', if_true: files('vhost-user-gpio.c'))
> specific_virtio_ss.add(when: ['CONFIG_VIRTIO_PCI', 'CONFIG_VHOST_USER_GPIO'], if_true: files('vhost-user-gpio-pci.c'))
> specific_virtio_ss.add(when: 'CONFIG_VHOST_VDPA_DEV', if_true: files('vdpa-dev.c'))
> @@ -43,7 +47,6 @@ virtio_pci_ss.add(when: 'CONFIG_VHOST_USER_VSOCK', if_true: files('vhost-user-vs
> virtio_pci_ss.add(when: 'CONFIG_VHOST_USER_BLK', if_true: files('vhost-user-blk-pci.c'))
> virtio_pci_ss.add(when: 'CONFIG_VHOST_USER_I2C', if_true: files('vhost-user-i2c-pci.c'))
> virtio_pci_ss.add(when: 'CONFIG_VHOST_USER_INPUT', if_true: files('vhost-user-input-pci.c'))
> -virtio_pci_ss.add(when: 'CONFIG_VHOST_USER_RNG', if_true: files('vhost-user-rng-pci.c'))
> virtio_pci_ss.add(when: 'CONFIG_VHOST_USER_SCSI', if_true: files('vhost-user-scsi-pci.c'))
> virtio_pci_ss.add(when: 'CONFIG_VHOST_SCSI', if_true: files('vhost-scsi-pci.c'))
> virtio_pci_ss.add(when: 'CONFIG_VHOST_USER_FS', if_true: files('vhost-user-fs-pci.c'))
Otherwise minus the struct formatting, the modelling looks good although given I
can't vouch for the virtio parts:
Acked-by: Mark Cave-Ayland <mark.cave-ayland at ilande.co.uk>
ATB,
Mark.
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