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 <longpe...@huawei.com>Implements the .instance_init and the .class_init interface.

Signed-off-by: Longpeng <longpe...@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