Re: [PATCH v1 4/4] vhost-vdpa:add callback function for configure interrupt

[Cindy Lu]

On Thu, Jan 14, 2021 at 12:46 PM Jason Wang <jasowang@redhat.com> wrote:
>
>
> On 2021/1/13 下午11:45, Cindy Lu wrote:
> > Add call back function for configure interrupt.
> > Set the notifier's fd to the kernel driver when vdpa start.
> > also set -1 when vdpa stop. then the kernel will release
> > the related聽resource聽
> >
> > Signed-off-by: Cindy Lu <lulu@redhat.com>
> > ---
> >   hw/virtio/trace-events            |  2 ++
> >   hw/virtio/vhost-vdpa.c            | 29 ++++++++++++++++++++++++++++-
> >   include/hw/virtio/vhost-backend.h |  4 ++++
> >   3 files changed, 34 insertions(+), 1 deletion(-)
> >
> > diff --git a/hw/virtio/trace-events b/hw/virtio/trace-events
> > index 2060a144a2..6710835b46 100644
> > --- a/hw/virtio/trace-events
> > +++ b/hw/virtio/trace-events
> > @@ -52,6 +52,8 @@ vhost_vdpa_set_vring_call(void *dev, unsigned int index, 
> > int fd) "dev: %p index:
> >   vhost_vdpa_get_features(void *dev, uint64_t features) "dev: %p features: 
> > 0x%"PRIx64
> >   vhost_vdpa_set_owner(void *dev) "dev: %p"
> >   vhost_vdpa_vq_get_addr(void *dev, void *vq, uint64_t desc_user_addr, 
> > uint64_t avail_user_addr, uint64_t used_user_addr) "dev: %p vq: %p 
> > desc_user_addr: 0x%"PRIx64" avail_user_addr: 0x%"PRIx64" used_user_addr: 
> > 0x%"PRIx64
> > +vhost_vdpa_set_config_call(void *dev, int *fd)"dev: %p fd: %p"
> > +
> >
> >   # virtio.c
> >   virtqueue_alloc_element(void *elem, size_t sz, unsigned in_num, unsigned 
> > out_num) "elem %p size %zd in_num %u out_num %u"
> > diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c
> > index 01d2101d09..1647bff8b0 100644
> > --- a/hw/virtio/vhost-vdpa.c
> > +++ b/hw/virtio/vhost-vdpa.c
> > @@ -467,20 +467,39 @@ static int vhost_vdpa_get_config(struct vhost_dev 
> > *dev, uint8_t *config,
> >       }
> >       return ret;
> >    }
> > +static void vhost_vdpa_config_notify_start(struct vhost_dev *dev,
> > +                                struct VirtIODevice *vdev, bool start)
> > +{
> > +    int fd, r;
> > +    if (start) {
> > +        fd = event_notifier_get_fd(&vdev->config_notifier);
> > +     } else {
> > +        fd = -1;
> > +     }
> > +    r = dev->vhost_ops->vhost_set_config_call(dev, &fd);
> > +    if (r) {
> > +        error_report("vhost_vdpa_config_notify_start error!");
> > +    }
>
>
> So on early version of kernel without config interrupt support. This
> will fail for sure. We need seek a way to make it work.
>
> Thanks
>
Thanks Jason I will test the old version and fix this one
>
> > +    return;
> >
> > +}
> >   static int vhost_vdpa_dev_start(struct vhost_dev *dev, bool started)
> >   {
> >       struct vhost_vdpa *v = dev->opaque;
> >       trace_vhost_vdpa_dev_start(dev, started);
> > +    VirtIODevice *vdev = dev->vdev;
> > +
> >       if (started) {
> >           uint8_t status = 0;
> >           memory_listener_register(&v->listener, &address_space_memory);
> >           vhost_vdpa_set_vring_ready(dev);
> >           vhost_vdpa_add_status(dev, VIRTIO_CONFIG_S_DRIVER_OK);
> >           vhost_vdpa_call(dev, VHOST_VDPA_GET_STATUS, &status);
> > -
> > +        /*set the configure interrupt call back*/
> > +        vhost_vdpa_config_notify_start(dev, vdev, true);
> >           return !(status & VIRTIO_CONFIG_S_DRIVER_OK);
> >       } else {
> > +        vhost_vdpa_config_notify_start(dev, vdev, false);
> >           vhost_vdpa_reset_device(dev);
> >           vhost_vdpa_add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE |
> >                                      VIRTIO_CONFIG_S_DRIVER);
> > @@ -546,6 +565,13 @@ static int vhost_vdpa_set_vring_call(struct vhost_dev 
> > *dev,
> >       return vhost_vdpa_call(dev, VHOST_SET_VRING_CALL, file);
> >   }
> >
> > +static int vhost_vdpa_set_config_call(struct vhost_dev *dev,
> > +                                       int *fd)
> > +{
> > +    trace_vhost_vdpa_set_config_call(dev, fd);
> > +    return vhost_vdpa_call(dev, VHOST_VDPA_SET_CONFIG_CALL, fd);
> > +}
> > +
> >   static int vhost_vdpa_get_features(struct vhost_dev *dev,
> >                                        uint64_t *features)
> >   {
> > @@ -611,4 +637,5 @@ const VhostOps vdpa_ops = {
> >           .vhost_get_device_id = vhost_vdpa_get_device_id,
> >           .vhost_vq_get_addr = vhost_vdpa_vq_get_addr,
> >           .vhost_force_iommu = vhost_vdpa_force_iommu,
> > +        .vhost_set_config_call = vhost_vdpa_set_config_call,
> >   };
> > diff --git a/include/hw/virtio/vhost-backend.h 
> > b/include/hw/virtio/vhost-backend.h
> > index 8a6f8e2a7a..1a2fee8994 100644
> > --- a/include/hw/virtio/vhost-backend.h
> > +++ b/include/hw/virtio/vhost-backend.h
> > @@ -125,6 +125,9 @@ typedef int (*vhost_get_device_id_op)(struct vhost_dev 
> > *dev, uint32_t *dev_id);
> >
> >   typedef bool (*vhost_force_iommu_op)(struct vhost_dev *dev);
> >
> > +typedef int (*vhost_set_config_call_op)(struct vhost_dev *dev,
> > +                                       int *fd);
> > +
> >   typedef struct VhostOps {
> >       VhostBackendType backend_type;
> >       vhost_backend_init vhost_backend_init;
> > @@ -170,6 +173,7 @@ typedef struct VhostOps {
> >       vhost_vq_get_addr_op  vhost_vq_get_addr;
> >       vhost_get_device_id_op vhost_get_device_id;
> >       vhost_force_iommu_op vhost_force_iommu;
> > +    vhost_set_config_call_op vhost_set_config_call;
> >   } VhostOps;
> >
> >   extern const VhostOps user_ops;
>