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

[longpeng2--- via <qemu-devel@nongnu.org>]

> -----Original Message-----
> From: Stefano Garzarella [mailto:sgarzare@redhat.com]
> Sent: Wednesday, January 5, 2022 7:29 PM
> To: Longpeng (Mike, Cloud Infrastructure Service Product Dept.)
> <longpeng2@huawei.com>
> Cc: stefanha@redhat.com; mst@redhat.com; jasowang@redhat.com;
> cohuck@redhat.com; pbonzini@redhat.com; Gonglei (Arei)
> <arei.gonglei@huawei.com>; Yechuan <yechuan@huawei.com>; Huangzhichao
> <huangzhichao@huawei.com>; qemu-devel@nongnu.org
> Subject: Re: [RFC 04/10] vdpa-dev: implement the instance_init/class_init
> interface
> 
> 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?
> 

Good catch, thanks.

> Thanks,
> Stefano