Re: [RFC 04/10] vdpa-dev: implement the instance_init/class_init interface

[Stefano Garzarella]

On Wed, Jan 05, 2022 at 08:58:54AM +0800, Longpeng(Mike) wrote:
> From: Longpeng <longpeng2@huawei.com>
>
> Implements the .instance_init and the .class_init interface.
>
> Signed-off-by: Longpeng <longpeng2@huawei.com>
> ---
> hw/virtio/vdpa-dev-pci.c     | 80 +++++++++++++++++++++++++++++++++++-
> hw/virtio/vdpa-dev.c         | 68 +++++++++++++++++++++++++++++-
> include/hw/virtio/vdpa-dev.h |  2 +
> 3 files changed, 146 insertions(+), 4 deletions(-)
>
> diff --git a/hw/virtio/vdpa-dev-pci.c b/hw/virtio/vdpa-dev-pci.c
> index a5a7b528a9..0af54a26d4 100644
> --- a/hw/virtio/vdpa-dev-pci.c
> +++ b/hw/virtio/vdpa-dev-pci.c
> @@ -23,14 +23,90 @@ struct VhostVdpaDevicePCI {
>     VhostVdpaDevice vdev;
> };
>
> +static uint32_t
> +vdpa_dev_pci_get_info(const char *name, uint64_t cmd, Error **errp)
> +{
> +    int device_fd;
> +    uint32_t val;
> +    int ret;
> +
> +    device_fd = qemu_open(name, O_RDWR, errp);
> +    if (device_fd == -1) {
> +        return (uint32_t)-1;
> +    }
> +
> +    ret = ioctl(device_fd, cmd, &val);
> +    if (ret < 0) {
> +        error_setg(errp, "vhost-vdpa-device-pci: cmd 0x%lx failed: %s",
> +                   cmd, strerror(errno));
> +        goto out;
> +    }
> +
> +out:
> +    close(device_fd);
> +    return val;
> +}
> +
> +static inline uint32_t
> +vdpa_dev_pci_get_devid(VhostVdpaDevicePCI *dev, Error **errp)
> +{
> +    return vdpa_dev_pci_get_info(dev->vdev.vdpa_dev,
> +                                 VHOST_VDPA_GET_DEVICE_ID, errp);
> +}
> +
> +static inline uint32_t
> +vdpa_dev_pci_get_vectors_num(VhostVdpaDevicePCI *dev, Error **errp)
> +{
> +    return vdpa_dev_pci_get_info(dev->vdev.vdpa_dev,
> +                                 VHOST_VDPA_GET_VECTORS_NUM, errp);
> +}
> +
> static void vhost_vdpa_device_pci_instance_init(Object *obj)
> {
> -    return;
> +    VhostVdpaDevicePCI *dev = VHOST_VDPA_DEVICE_PCI(obj);
> +
> +    virtio_instance_init_common(obj, &dev->vdev, sizeof(dev->vdev),
> +                                TYPE_VHOST_VDPA_DEVICE);
> +    object_property_add_alias(obj, "bootindex", OBJECT(&dev->vdev),
> +                              "bootindex");
> +}
> +
> +static Property vhost_vdpa_device_pci_properties[] = {
> +    DEFINE_PROP_END_OF_LIST(),
> +};
> +
> +static void
> +vhost_vdpa_device_pci_realize(VirtIOPCIProxy *vpci_dev, Error **errp)
> +{
> +    VhostVdpaDevicePCI *dev = VHOST_VDPA_DEVICE_PCI(vpci_dev);
> +    DeviceState *vdev = DEVICE(&dev->vdev);
> +    uint32_t devid;
> +    uint32_t vectors;
> +
> +    devid = vdpa_dev_pci_get_devid(dev, errp);
> +    if (*errp) {
> +        return;
> +    }
> +
> +    vectors = vdpa_dev_pci_get_vectors_num(dev, errp);
> +    if (*errp) {
> +        return;
> +    }
> +
> +    vpci_dev->class_code = virtio_pci_get_class_id(devid);
> +    vpci_dev->pdev_id = virtio_pci_get_pci_devid(devid);
> +    vpci_dev->nvectors = vectors;
> +    qdev_realize(vdev, BUS(&vpci_dev->bus), errp);
> }
>
> static void vhost_vdpa_device_pci_class_init(ObjectClass *klass, void *data)
> {
> -    return;
> +    DeviceClass *dc = DEVICE_CLASS(klass);
> +    VirtioPCIClass *k = VIRTIO_PCI_CLASS(klass);
> +
> +    set_bit(DEVICE_CATEGORY_MISC, dc->categories);
> +    device_class_set_props(dc, vhost_vdpa_device_pci_properties);
> +    k->realize = vhost_vdpa_device_pci_realize;
> }
>
> static const VirtioPCIDeviceTypeInfo vhost_vdpa_device_pci_info = {
> diff --git a/hw/virtio/vdpa-dev.c b/hw/virtio/vdpa-dev.c
> index f4f92b90b0..790117fb3b 100644
> --- a/hw/virtio/vdpa-dev.c
> +++ b/hw/virtio/vdpa-dev.c
> @@ -15,16 +15,80 @@
> #include "sysemu/sysemu.h"
> #include "sysemu/runstate.h"
>
> -static void vhost_vdpa_device_class_init(ObjectClass *klass, void *data)
> +static void vhost_vdpa_device_realize(DeviceState *dev, Error **errp)
> {
>     return;
> }
>
> -static void vhost_vdpa_device_instance_init(Object *obj)
> +static void vhost_vdpa_device_unrealize(DeviceState *dev)
> +{
> +    return;
> +}
> +
> +static void
> +vhost_vdpa_device_get_config(VirtIODevice *vdev, uint8_t *config)
> +{
> +    return;
> +}
> +
> +static void
> +vhost_vdpa_device_set_config(VirtIODevice *vdev, const uint8_t *config)
> {
>     return;
> }
>
> +static uint64_t vhost_vdpa_device_get_features(VirtIODevice *vdev,
> +                                               uint64_t features,
> +                                               Error **errp)
> +{
> +    return (uint64_t)-1;
> +}
> +
> +static void vhost_vdpa_device_set_status(VirtIODevice *vdev, uint8_t status)
> +{
> +    return;
> +}
> +
> +static Property vhost_vdpa_device_properties[] = {
> +    DEFINE_PROP_STRING("vdpa-dev", VhostVdpaDevice, vdpa_dev),
> +    DEFINE_PROP_END_OF_LIST(),
> +};
> +
> +static const VMStateDescription vmstate_vhost_vdpa_device = {
> +    .name = "vhost-vdpa-device",
> +    .minimum_version_id = 1,
> +    .version_id = 1,
> +    .fields = (VMStateField[]) {
> +        VMSTATE_VIRTIO_DEVICE,
> +        VMSTATE_END_OF_LIST()
> +    },
> +};
> +
> +static void vhost_vdpa_device_class_init(ObjectClass *klass, void *data)
> +{
> +    DeviceClass *dc = DEVICE_CLASS(klass);
> +    VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
> +
> +    device_class_set_props(dc, vhost_vdpa_device_properties);
> +    dc->desc = "VDPA-based generic PCI device assignment";

IIUC, this should be the description of the generic vhost vDPA device, 
not the PCI implementation, right?

Thanks,
Stefano