Re: [RFC PATCH v9 19/23] vdpa: Extract get features part from vhost_vdpa_get_max_queue_pairs

[Jason Wang]

在 2022/7/7 02:40, Eugenio Pérez 写道:
> To know the device features is needed for CVQ SVQ, so SVQ knows if it
> can handle all commands or not. Extract from
> vhost_vdpa_get_max_queue_pairs so we can reuse it.
>
> Signed-off-by: Eugenio Pérez <eperezma@redhat.com>


Acked-by: Jason Wang <jasowang@redhat.com>


> ---
>   net/vhost-vdpa.c | 30 ++++++++++++++++++++----------
>   1 file changed, 20 insertions(+), 10 deletions(-)
>
> diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c
> index df1e69ee72..b0158f625e 100644
> --- a/net/vhost-vdpa.c
> +++ b/net/vhost-vdpa.c
> @@ -219,20 +219,24 @@ static NetClientState *net_vhost_vdpa_init(NetClientState 
> *peer,
>       return nc;
>   }
>   
> -static int vhost_vdpa_get_max_queue_pairs(int fd, int *has_cvq, Error **errp)
> +static int vhost_vdpa_get_features(int fd, uint64_t *features, Error **errp)
> +{
> +    int ret = ioctl(fd, VHOST_GET_FEATURES, features);
> +    if (ret) {
> +        error_setg_errno(errp, errno,
> +                         "Fail to query features from vhost-vDPA device");
> +    }
> +    return ret;
> +}
> +
> +static int vhost_vdpa_get_max_queue_pairs(int fd, uint64_t features,
> +                                          int *has_cvq, Error **errp)
>   {
>       unsigned long config_size = offsetof(struct vhost_vdpa_config, buf);
>       g_autofree struct vhost_vdpa_config *config = NULL;
>       __virtio16 *max_queue_pairs;
> -    uint64_t features;
>       int ret;
>   
> -    ret = ioctl(fd, VHOST_GET_FEATURES, &features);
> -    if (ret) {
> -        error_setg(errp, "Fail to query features from vhost-vDPA device");
> -        return ret;
> -    }
> -
>       if (features & (1 << VIRTIO_NET_F_CTRL_VQ)) {
>           *has_cvq = 1;
>       } else {
> @@ -262,10 +266,11 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char 
> *name,
>                           NetClientState *peer, Error **errp)
>   {
>       const NetdevVhostVDPAOptions *opts;
> +    uint64_t features;
>       int vdpa_device_fd;
>       g_autofree NetClientState **ncs = NULL;
>       NetClientState *nc;
> -    int queue_pairs, i, has_cvq = 0;
> +    int queue_pairs, r, i, has_cvq = 0;
>   
>       assert(netdev->type == NET_CLIENT_DRIVER_VHOST_VDPA);
>       opts = &netdev->u.vhost_vdpa;
> @@ -279,7 +284,12 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char 
> *name,
>           return -errno;
>       }
>   
> -    queue_pairs = vhost_vdpa_get_max_queue_pairs(vdpa_device_fd,
> +    r = vhost_vdpa_get_features(vdpa_device_fd, &features, errp);
> +    if (r) {
> +        return r;
> +    }
> +
> +    queue_pairs = vhost_vdpa_get_max_queue_pairs(vdpa_device_fd, features,
>                                                    &has_cvq, errp);
>       if (queue_pairs < 0) {
>           qemu_close(vdpa_device_fd);