Re: [Qemu-devel] [PATCH v4 4/4] contrib/vhost-user-blk: introduce a vhost-user-blk sample application

[Paolo Bonzini]

On 19/10/2017 07:24, Changpeng Liu wrote:
> 
> +}
> +
> +static void
> +vub_flush(VubReq *req)
> +{
> +    VubDev *vdev_blk = req->vdev_blk;
> +
> +    if (vdev_blk->blk_fd) {
> +        fsync(vdev_blk->blk_fd);
> +    }
> +}
> +

No need to check the file descriptor---vub_readv and vub_writev aren't
checking it either.  Also please use fdatasync instead of fsync.

> +static uint64_t
> +vub_get_features(VuDev *dev)
> +{
> +    return 1ull << VIRTIO_BLK_F_SIZE_MAX |
> +           1ull << VIRTIO_BLK_F_SEG_MAX |
> +           1ull << VIRTIO_BLK_F_TOPOLOGY |
> +           1ull << VIRTIO_BLK_F_BLK_SIZE |
> +           1ull << VIRTIO_F_VERSION_1 |
> +           1ull << VHOST_USER_F_PROTOCOL_FEATURES;
> +}

VIRTIO_BLK_F_FLUSH is missing.

Thanks,

Paolo